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This study in Singapore analysed the incubation periods of the following SARS-CoV-2 variants: Wuhan-Hu-1, Delta, and Omicron. Three pandemic waves were examined: Wuhan-Hu-1 (January 2020–March 2021), Delta (May–October 2021), and Omicron (January–June 2022). Data from the SingHealth COVID-19 registry, covering patients from 23 January 2020 to 10 June 2022, were used to calculate incubation periods during the three time periods. The study found median incubation periods of 11 days for Wuhan-Hu-1, 3 days for Delta, and 3 days for Omicron (p-value: <0.001). This study highlighted the impact of different containment measures and the importance of robust EMR systems for tracking and managing infectious diseases. Key challenges included accurate contact tracing and IT infrastructure capabilities. The findings support the use of EMR data for future infectious disease preparedness in Singapore. [ABSTRACT FROM AUTHOR]

BACKGROUND: Early blight is one of the main diseases that causes serious pepper yield and quality reduction. The identification of the presymptomatic features during the incubation period is of great research significance, in that scientific prevention measures in the incubation period may effectively reduce the loss of peppers. RESULTS: The present study confirms the feasibility of the identification of presymptomatic features in pepper early blight by infrared thermography during the incubation period. The infrared thermal images of pepper blades were captured during the whole incubation period in our experiment. Evaluation parameters such as temperature uniformity (U) and the variation coefficient (C) were established by infrared thermal images for the blade temperature field. Evaluation parameters such as temperature uniformity U and variation coefficient C of pepper blades change during the time from being inoculated to significant morbidity. For cases of stabbing inoculation, there were no relatively obvious symptoms in visible light images until 96 h after inoculation, whereas some presymptomatic features appeared in infrared thermal images at 60 h after inoculation. Based on the uniformity changes (δU) and the variation coefficient changes (δC) in the temperature field distribution, the characteristic polynomial (CP)‐GBDT model has been established by optimizing the gradient boosting decision tree (GBDT) model. Compared with the GBDT mode, the CP‐GBDT model accuracy increased from 87.5% to 91.7% on the test set. CONCLUSION: Evaluation parameters such as temperature uniformity U and variation coefficient C can be used to effectively characterize the presymptomatic features of pepper early blight by infrared thermography during the incubation period. The results of the present study can provide a reference for the detection of crop diseases in the incubation period. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background Development of rapid bacterial identification from blood cultures has been an area of intense study in diagnostic microbiology. Shortened turnaround time coupled with antimicrobial stewardship interventions have been shown to improve patient outcomes and decrease healthcare-associated costs. Objectives We report the validation of a short incubation method for Gram-positive and Gram-negative bacterial identification utilizing MALDI-TOF MS without additional instrumentation, processing or cost compared with current practice. Methods Prospective, observational, single-centre study in a quaternary care academic hospital encompassing 376 blood cultures subjected to bacterial identification after short incubation periods of 3–4 and 6–8 h. Results There was 97.5% species-level identification agreement with tests undertaken after 3–4 h incubation with 83.6% isolates identified, and 99.7% species-level identification agreement after 6–8 h incubation with 96.7% isolates identified. Conclusions The short incubation method provides a rapid MALDI-TOF MS bacterial identification method, reducing turnaround time by 10–18 h compared with standard practice without additional cost, processing or instrumentation. [ABSTRACT FROM AUTHOR]

BACKGROUND: Early identification of patients requiring ventilator support will be beneficial for the outcomes of botulism. The present study aimed to establish a new scoring system to predict mechanical ventilation (MV) for botulism patients. METHODS: A single-center retrospective study was conducted to identify risk factors associated with MV in botulism patients from 2007 to 2022. Univariate analysis and multivariate logistic regression analysis were used to screen out risk factors for constructing a prognostic scoring system. The area under the receiver operating characteristic (ROC) curve was calculated. RESULTS: A total of 153 patients with botulism (66 males and 87 females, with an average age of 43 years) were included. Of these, 49 patients (32.0%) required MV, including 21 (13.7%) with invasive ventilation and 28 (18.3%) with non-invasive ventilation. Multivariate analysis revealed that botulinum toxin type, pneumonia, incubation period, degree of hypoxia, and severity of muscle involvement were independent risk factors for MV. These risk factors were incorporated into a multivariate logistic regression analysis to establish a prognostic scoring system. Each risk factor was scored by allocating a weight based on its regression coefficient and rounded to whole numbers for practical utilization ([botulinum toxin type A: 1], [pneumonia: 2], [incubation period =1 day: 2], [hypoxia <90%: 2], [severity of muscle involvement: grade II, 3; grade III, 7; grade IV, 11]). The scoring system achieved an area under the ROC curve of 0.82 (95% CI 0.75-0.89, P<0.001). At the optimal threshold of 9, the scoring system achieved a sensitivity of 83.7% and a specificity of 70.2%. CONCLUSION: Our study identified botulinum toxin type, pneumonia, incubation period, degree of hypoxia, and severity of muscle involvement as independent risk factors for MV in botulism patients. A score =9 in our scoring system is associated with a higher likelihood of requiring MV in botulism patients. This scoring system needs to be validated externally before it can be applied in clinical settings. [ABSTRACT FROM AUTHOR]

Reproduction of the pancake tortoise in the wild has remained poorly known over the decades. This study fills the knowledge gap by investigating the reproductive ecology of the species in its natural habitats in Kenya. Data were collected using the time‐constrained search‐and‐seize method, group‐level scan sampling, radio tracking, and camera‐trapping. Our observations revealed a total of 19 mating events that occurred between December and April, predominantly during the rainy seasons. Mating duration averaged 15.2 ± 2.4 min. Male–male aggression was observed during the mating season, with the dominant male keeping off all other males and mating with the resident females. Nest preparation events occurred between April and June. Nine nesting events were recorded, but in only five of them was an egg deposited. The nests were dug in loose soil, appeared almost circular, and measured 8.4 ± 0.9 cm wide and 7.0 ± 0.1 cm deep (n = 7). The average clutch size was one egg. The eggs were white, hard‐shelled, oval, and elongated measuring 4.4 ± 0.4 cm long, 2.7 ± 0.04 cm wide and weighed 17 ± 0.6 g (n = 3). Incubation period lasted 177 ± 5.7 days (n = 2), and hatching coincided with the onset of the short rainy season in November, aligned with the availability of abundant food for the tortoises. The hatchlings were minimally wider than long, having an average straight carapace length of 4.5 ± 0.6 cm, an average width of 4.5 ± 0.4 cm, and on average weighed 14.7 ± 3.7g, (n = 9). They remained near the nest site for 4–5 days before relocating to tiny rock crevices away from the adult tortoise crevices. Egg and hatchling predation was high, with four of the total of six eggs, observed after they were laid, being destroyed. Three juveniles, out of nine, were also eaten by predators. These findings contribute useful information for the formulation of effective conservation and management strategies for this critically endangered species. [ABSTRACT FROM AUTHOR]

We used published data from outbreak investigations of monkeypox virus clade I in the Democratic Republic of the Congo to estimate the distributions of critical epidemiological parameters. We estimated a mean incubation period of 9.9 days (95% credible interval [CrI] 8.5–11.5 days) and a mean generation time of 17.2 days (95% CrI 14.1–20.9 days) or 11.3 days (95% CrI 9.4–14.0 days), depending on the considered dataset. Presymptomatic transmission was limited. Those estimates suggest generally slower transmission dynamics in clade I than in clade IIb. The time-varying reproduction number for clade I in the Democratic Republic of the Congo was estimated to be below the epidemic threshold in the first half of 2024. However, in the South Kivu Province, where the newly identified subclade Ib has been associated with sustained human-to-human transmission, we estimated an effective reproduction number above the epidemic threshold (95% CrI 0.96–1.27).

This study in Singapore analysed the incubation periods of the following SARS-CoV-2 variants: Wuhan-Hu-1, Delta, and Omicron. Three pandemic waves were examined: Wuhan-Hu-1 (January 2020–March 2021), Delta (May–October 2021), and Omicron (January–June 2022). Data from the SingHealth COVID-19 registry, covering patients from 23 January 2020 to 10 June 2022, were used to calculate incubation periods during the three time periods. The study found median incubation periods of 11 days for Wuhan-Hu-1, 3 days for Delta, and 3 days for Omicron (p-value:

Understanding changes in the transmission dynamics of mpox requires comparing recent estimates of key epidemiologic parameters with historical data. We derived historical estimates for the incubation period and serial interval for mpox and contrasted them with pooled estimates from the 2022 outbreak. Our findings show the pooled mean infection-to-onset incubation period was 8.1 days for the 2022 outbreak and 8.2 days historically, indicating the incubation periods remained relatively consistent over time, despite a shift in the major mode of transmission. However, we estimated the onset-to-onset serial interval at 8.7 days using 2022 data, compared with 14.2 days using historical data. Although the reason for this shortening of the serial interval is unclear, it may be because of increased public health interventions or a shift in the mode of transmission. Recognizing such temporal shifts is essential for informed response strategies, and public health measures remain crucial for controlling mpox and similar future outbreaks.

Mud crabs are common edible crustaceans, which are fished along the coasts of India. Scylla tranquebarica (Fabricius 1798), commonly called green crab is one of the most economically important portunid crab in India. The study was carried out to determine the sex ratio, maturation and spawning, gonadosomatic index, fecundity and egg diameter. Sex ratio of 1 female to 1.3 male gave good results. Size at first maturity was observed at 11 cm carapace width (CW) in males and 10 cm (CW) in females. The highest GSI values in males (6.17) and females (5.12) were observed in the month of October. The maximum number of eggs produced by the females was up to 5 million. The egg diameter was recorded in the range of 0.69 to 0.76 mm. The incubation period was 11-13 days. The hatching success average percentage was recorded as 80%. For the incubation and larval rearing of mud crab, Scylla tranquibarica, the optimum requirement of water temperature and salinity were recorded as 28°C and 30 ppt, respectively. [ABSTRACT FROM AUTHOR]

Three hybrid populations (F1) of Coffea arabica were evaluated under field and laboratory conditions, derived from sources carrying the SH1 coffee leaf rust (CLR) resistance gene and the CX.2385 line, obtained from the Caturra × Timor Hybrid CIFC-1343. The results obtained under controlled conditions and analyzed using survival curves allowed to estimate the probable times (p < 0.05) for the development of symptoms associated with CLR in the plants of populations evaluated. Phenotypic variation was observed as a defense response to Hemileia vastatrix infection, and plants with incomplete resistance to CLR were identified via an evaluation using the increasing lesions scale. The plants with incomplete resistance exhibited a delay in the development of the incubation period and an absence of the development of the dormancy period. Data suggest that when resistance genes in the sources are defeated by compatible strains, their recombination can give rise to new levels of resistance in the progeny. Additionally, the detached leaf methodology is recommended as an alternative to preselect genotypes with resistance to CLR, thus reducing the number of plants that are finally planted for field evaluations. [ABSTRACT FROM AUTHOR]

Abstract Background Incubation behaviour, an instinct for natural breeding in poultry, is strictly controlled by the central nervous system and multiple neuroendocrine hormones and neurotransmitters, and is closely associated with the cessation of egg laying. Therefore, it is essential for the commercial poultry industry to clarify the molecular regulation mechanism of incubation behaviour. Here, we used high-throughput sequencing technology to examine the pituitary transcriptome of Changshun green-shell laying hen, a local breed from Guizhou province, China, with strong broodiness, in two reproductive stages, including egg-laying phase (LP) and incubation phase (BP). We also analyze the differences in gene expression during the transition from egg-laying to incubation, and identify critical pathways and candidate genes involved in controlling the incubation behaviour in the pituitary. Results In this study, we demonstrated that a total of 2089 differently expressed genes (DEGs) were identified in the pituitary, including 842 up-regulated and 1247 down-regulated genes. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that steroid biosynthesis pathway and neuroactive ligand-receptor interaction were significantly enriched based on DEGs commonly identified in pituitary. Further analysis revealed that SRC, ITGB4, ITGB3, PIK3R3 and DRD2 may play crucial roles in the regulation of incubation behaviour. Conclusions We identified 2089 DEGs and the key signaling pathways which may be closely correlated with incubation in Changshun green-shell laying hens, and clarified the molecular regulation mechanism of incubation behaviour. Our results indicate the complexity and variety of differences in reproductive behaviour of different chicken breeds.

Abstract Background The latent and incubation periods characterize the transmission of infectious viruses and are the basis for the development of outbreak prevention and control strategies. However, systematic studies on the latent period and associated factors with the incubation period for SAS-CoV-2 variants are still lacking. We inferred the two durations of Delta, BA.1, and BA.2 cases and analyzed the associated factors. Methods The Delta, BA.1, and BA.2 (and its lineages BA.2.2 and BA.2.76) cases with clear transmission chains and infectors from 10 local SAS-CoV-2 epidemics in China were enrolled. The latent and incubation periods were fitted by the Gamma distribution, and associated factors were analyzed using the accelerated failure time model. Results The mean latent period for 672 Delta, 208 BA.1, and 677 BA.2 cases was 4.40 (95%CI: 4.24 ~ 4.63), 2.50 (95%CI: 2.27 ~ 2.76), and 2.58 (95%CI: 2.48 ~ 2.69) days, respectively, with 85.65% (95%CI: 83.40 ~ 87.77%), 97.80% (95%CI: 96.35 ~ 98.89%), and 98.87% (95%CI: 98.40 ~ 99.27%) of them starting to shed viruses within 7 days after exposure. In 405 Delta, 75 BA.1, and 345 BA.2 symptomatic cases, the mean latent period was 0.76, 1.07, and 0.79 days shorter than the mean incubation period [5.04 (95%CI: 4.83 ~ 5.33), 3.42 (95%CI: 3.00 ~ 3.89), and 3.39 (95%CI: 3.24 ~ 3.55) days], respectively. No significant difference was observed in the two durations between BA.1 and BA.2 cases. After controlling for the sex, clinical severity, vaccination history, number of infectors, the length of exposure window and shedding window, the latent period [Delta: exp(β) = 0.81, 95%CI: 0.66 ~ 0.98, p = 0.034; Omicron: exp(β) = 0.82, 95%CI: 0.71 ~ 0.94, p = 0.004] and incubation period [Delta: exp(β) = 0.69, 95%CI: 0.55 ~ 0.86, p

Biochars were produced at 350 °C and applied at varying rates (0, 52, 104, and 156 Mg ha−1 and incubation times up to 120 days. Both biochars and limestone significantly improved soil properties like pH, electrical conductivity, cation exchange capacity (CEC), and nutrient availability. Limestone proved most effective, raising pH by 1.3 units on average and increasing EC and CEC, followed by Cadia purpurea- and Tarchonanthus camphoratus-based biochars. Biochars also increased pH, with Cadia purpurea showing the greatest effect (up to a 1.49 unit increase at the highest rate of application). These findings suggest biochar from these expansive plants holds promise for improving acidic soils. However, the optimal application rate, incubation times, and type of amendment (biochar or limestone) likely depend on specific soil characteristics and goals. Further research is needed to explore long-term effects, combined amendment approaches, and cost-effectiveness for long-term soil health, agricultural productivity, and environmental well-being.

Recycling of phosphorus (P) from feedstocks to soils can provide sustainability in agriculture. In our incubation study, we investigated the effects of adding cow manure-derived vermicompost (CMV), cow manure (CM), sugarcane trash biochar (STB), and triple super phosphate (TSP) to extractable P in a sandy loam soil. P was added to the soil at rates of 0, 50, 100, 200, and 300 mg kg−1 based on their total P contents. The amended soils were incubated for 1, 4, 8, and 16 weeks (wk) at room temperature and extractable P samples were measured (by water, Olsen, Mehlich-3 and Bray and Kurtz) and soil pH was monitored. After 1 wk of incubation, the extractable P values were 1.4 mg kg−1 with STB at the smallest while the highest was 79 mg kg−1 with TSP. The corresponding P values in the CMV and CM amended soils were 33 mg kg−1 and 31 mg kg−1. The reductions of extractable P from 1 to 16 wks of incubation were 40%, 35%, and 80% in the CMV, CM and TSP amended soils, respectively, while they increased from 1.43 mg kg−1 to 6.05 mg kg−1 ((320%) in the STB amended soil. Among the amendments, a significant positive relationship was observed between extractable P and the pH in soils amended with STB. The findings revealed that varying P extractability in soils depends on amendment types and duration of incubation. Sugarcane trash biochar did not exhibit an ability to substitute inorganic P fertilizer for assessing bioavailable P. [ABSTRACT FROM AUTHOR]

The boreal owl (Aegolius funereus) has a circumpolar distribution, typically inhabit extensive conifer forest of higher age classes in the northern hemisphere. Breeding biology, reproductive strategies, and behavioural ecology of these nocturnal birds are well studied in Europe and North America. However, the knowledge of the subspecies of boreal owl (A. f. beickianus) in the coniferous forests at high mountainous altitude of the Qinghai-Tibet Plateau is still limited. We spent 10 years studying the breeding biology of A. f. beickianus in Lian Hua Shan Nature Reserve (Gansu Province), where we could first confirm the occurrence of this small forest dwelling owl in 1995. During breeding seasons (2003-2009, 2017-2019), we checked nest boxes and recorded the basic breeding data. Thereby a total of 51 broods were found with an average of 5.1 ± 1.7 broods per year. The mean egg mass and volume was 12.42 ± 1.36 g and 12.85 ± 0.79 mm³, respectively. Mean clutch size per brood was 2.61 ± 0.64. The mean number of fledglings was 1.25 ± 0.31 per nesting attempt and 2.07 ± 0.38 per successful brood. Nestling period lasted 35.75 ± 2.80 days in total, but was divided in two stages: in the first stage, which lasted 16.75 ± 1.48 days, the female stood in the breeding hole with its nestlings. In the second stage, which lasted 17 ± 4.34 days until the fledglings left their nest, the female stood outside the hole. The individual fledglings left the nesting site in intervals of 2.55 ± 1.92 days. [ABSTRACT FROM AUTHOR]

Dengue is a mosquito-borne viral infection that triggers a series of intracellular events in the host immune system, which may result in an invasion of the virus into the host and cause illness with a spectrum of severity. Depending on the degree of the infection, mild to severe clinical symptoms appear when the T-cell and B-cell-initiated immune responses fail to eradicate the virus particles and subsequently become compromised. Here, we propose a mathematically tractable simple model that exhibits important biological features of dengue infection. Dynamical analysis of our model explores the factors influencing viral persistence in the body over an extended period. To investigate plausible variability in viral dynamics in different hosts, we perform stochastic simulations of our model using Gillespie's algorithm. Our simulation results recapitulate the distribution of the intrinsic incubation period, daily viral load, and the day of peak viremia. In addition, we observe that the invasion probability of the virus into the host is correlated with the initial virus population injected by the mosquito. However, considering the biting behavior of Aedes mosquitoes, a lower initial virus injection could end up increasing the epidemic potential of the virus. [ABSTRACT FROM AUTHOR]

Background: Incubation behaviour, an instinct for natural breeding in poultry, is strictly controlled by the central nervous system and multiple neuroendocrine hormones and neurotransmitters, and is closely associated with the cessation of egg laying. Therefore, it is essential for the commercial poultry industry to clarify the molecular regulation mechanism of incubation behaviour. Here, we used high-throughput sequencing technology to examine the pituitary transcriptome of Changshun green-shell laying hen, a local breed from Guizhou province, China, with strong broodiness, in two reproductive stages, including egg-laying phase (LP) and incubation phase (BP). We also analyze the differences in gene expression during the transition from egg-laying to incubation, and identify critical pathways and candidate genes involved in controlling the incubation behaviour in the pituitary. Results: In this study, we demonstrated that a total of 2089 differently expressed genes (DEGs) were identified in the pituitary, including 842 up-regulated and 1247 down-regulated genes. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that steroid biosynthesis pathway and neuroactive ligand-receptor interaction were significantly enriched based on DEGs commonly identified in pituitary. Further analysis revealed that SRC, ITGB4, ITGB3, PIK3R3 and DRD2 may play crucial roles in the regulation of incubation behaviour. Conclusions: We identified 2089 DEGs and the key signaling pathways which may be closely correlated with incubation in Changshun green-shell laying hens, and clarified the molecular regulation mechanism of incubation behaviour. Our results indicate the complexity and variety of differences in reproductive behaviour of different chicken breeds. [ABSTRACT FROM AUTHOR]

ABSTRACT: Incubation behavior in chickens is closely associated with hypothalamus. Here, RNA sequencing of hypothalamus from Changshun green-shell laying hens, an indigenous chicken breed from China, in egg-laying period (LP) and incubation period (BP) was conducted to identify critical pathways and candidate genes involved in controlling the incubation behavior in hypothalamus. A total of 637 up-regulated and 305 down-regulated differently expressed genes (DEGs) were identified in chicken hypothalamus between LP and BP groups. Gene ontology term (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis further revealed that neuroactive ligand-receptor interaction, hippo signaling pathway, and focal adhesion were significantly enriched. Five candidate genes (POMC, IGF1R, CHAD, VCL, and MYL9) were suggested to play crucial roles in the regulation of chicken incubation behavior. Our results further indicated the complexity of reproductive behavior of different chicken breeds.

Summary: Background: Limited knowledge exists regarding behavioral and biomarker shifts during the period from respiratory infection exposure to testing decisions (the diagnostic decision period), a key phase affecting transmission dynamics and public health strategy development. This study aims to examine the changes in behavior and biomarkers during the diagnostic decision period for COVID-19, influenza, and group A streptococcus (GAS). Methods: We analyzed data from a two-year prospective cohort study involving 4795 participants in Israel, incorporating smartwatch data, self-reported symptoms, and medical records. Our analysis focused on three critical phases: the digital incubation period (from exposure to physiological anomalies detected by smartwatches), the symptomatic incubation period (from exposure to onset of symptoms), and the diagnostic decision period for influenza, COVID-19, and GAS. Findings: The delay between initial symptom reporting and testing was 39 [95% confidence interval (CI): 34–45] hours for influenza, 53 [95% CI: 49–58] hours for COVID-19, and 38 [95% CI: 32–46] hours for GAS, with 73 [95% CI: 67–78] hours from anomalies in heart measures to symptom onset for influenza, 23 [95% CI: 18–27] hours for COVID-19, and 62 [95% CI: 54–68] hours for GAS. Analyzing the entire course of infection of each individual, the greatest changes in heart rates were detected 67.6 [95% CI: 62.8–72.5] hours prior to testing for influenza, 64.1 [95% CI: 61.4–66.7] hours prior for COVID-19, and 58.2 [95% CI: 52.1–64.2] hours prior for GAS. In contrast, the greatest reduction in physical activities and social contacts occurred after testing. Interpretation: These findings highlight the delayed response of patients in seeking medical attention and reducing social contacts and demonstrate the transformative potential of smartwatches for identifying infection and enabling timely public health interventions. Funding: This work was supported by the European Research Council, project #949850, the Israel Science Foundation (ISF), grant No. 3409/19, within the Israel Precision Medicine Partnership program, and a Koret Foundation gift for Smart Cities and Digital Living.

Objective: Rare disease Background: Leprosy, also known as Hansen's disease, is a neglected tropical disease with low prevalence in the United States. The disease's long incubation period can cause delayed presentation, and most affected individuals have a history of travel or work in leprosy-endemic regions. The immune response to Mycobacterium leprae determines the clinical characteristics of leprosy, with tuberculoid leprosy being characterized by well-defined granulomas and involvement of peripheral nerves. The recommended treatment is a combination of dapsone and rifampin for 12 months. Case Report: A 78-year-old man with a history of extensive travel to Africa and Asia 50 years ago, presented with a nontender, non-pruritic, and hypopigmented skin lesion on his left knee. Biopsy results confirmed granulomatous inflammation and the presence of Mycobacterium leprae, leading to a diagnosis of tuberculoid/paucibacillary leprosy. The patient received dapsone and rifampin treatment, which resulted in symptom improvement. Conclusions: The patient's long incubation period of 50 years between exposure and symptom onset is remarkable and possibly one of the longest reported for tuberculoid leprosy. It emphasizes the importance of considering leprosy in cases with an extensive travel history and long incubation periods. Our patient's case presented contradictory staining results, suggesting potential sampling variation or a rare mixed leprosy form. Based on his clinical findings, he was diagnosed with tuberculoid leprosy. Early diagnosis and treatment are crucial to prevent irreversible nerve damage and improve patient outcomes. Healthcare providers should be vigilant in acquiring a detailed travel history to facilitate early diagnosis and appropriate management of leprosy cases. [ABSTRACT FROM AUTHOR]

Objectives The aims of this study were: (i) to assess the ability of the meropenem screening breakpoint as part of the screening rapid antimicrobial susceptibility testing (sRAST) of EUCAST for the detection of OXA-48 carbapenemase-producing Klebsiella pneumoniae directly from positive blood cultures (BCs); and (ii) to evaluate the inclusion of ertapenem and temocillin discs into the sRAST to enhance the detection of OXA-48-producing isolates. Methods BC bottles were spiked with a total of 117 K. pneumoniae isolates, including 77 previously characterized OXA-48 producers and 40 non-OXA-48 producers. Disc diffusion assays were directly performed from positive BCs with meropenem (10 µg), ertapenem (10 µg) and temocillin (30 µg) discs, and inhibition zones were manually measured after 4, 6 and 8 h of incubation. The screening cut-off values of sRAST were applied to evaluate their capability in detecting OXA-48-producing isolates. Receiver operating characteristic curves were constructed to illustrate the performance efficacy of the disc diffusion assays to detect OXA-48 producers. Results The meropenem cut-off values of sRAST only detected 90.91% of the OXA-48-producing isolates after 6 and 8 h of incubation. With the proposed cut-off points for ertapenem [<19 mm (4/6 h) and <20 mm (8 h)] and temocillin [<10 mm (4 h) and <11 mm (6/8 h)], all OXA-48-positive isolates were detected without any false-positive results at any reading time. Conclusions In healthcare settings with a high prevalence of OXA-48 producers, the inclusion of ertapenem and temocillin discs in the sRAST procedure may improve the detection of OXA-48-producing K. pneumoniae isolates directly from positive BCs, providing reliable results after only a 4 h incubation period. [ABSTRACT FROM AUTHOR]

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We derive a reaction–diffusion model with time-delayed nonlocal effects to study an epidemic's spatial spread numerically. The model describes infected individuals in the latent period using a structured model with diffusion. The epidemic model assumes that infectious individuals are subject to containment measures. To simulate the model in two-dimensional space, we use the continuous Runge–Kutta method of the fourth order and the discrete Runge–Kutta method of the third order with six stages. The numerical results admit the existence of traveling wave solutions for the proposed model. We use the COVID-19 epidemic to conduct numerical experiments and investigate the minimal speed of spread of the traveling wave front. The minimal spreading speeds of COVID-19 are found and discussed. Also, we assess the power of containment measures to contain the epidemic. The results depict a clear drop in the spreading speed of the traveling wave front after applying containment measures to at-risk populations. [ABSTRACT FROM AUTHOR]

Lassa fever is a deadly viral disease whose incubation period ranges from six to twenty-one days and about eighty percent of Lassa virus infection is asymptomatic. A deterministic model was formulated to quantify the transmission dynamics of the disease under isolation and treatment of the isolated asymptomatic and symptomatic humans for effective management and possible elimination of the disease. The solutions of the model were shown to be positive and bounded. Equilibrium analysis was conducted and both the disease-free and the endemic equilibria were derived. The threshold quantity for disease elimination, R0, was also obtained and used to derive conditions for the existence of stability of the eqilibria. The quantity was also employed to examine the sensitivity of the model parameters to disease propagation and reduction. The theoretical analysis was then complemented with the quantitative analysis by adopting a set of realistic values for the model parame- ters in order to show the effect of isolation and treatment on the spread and fatality of Lassa fever. Results from the quantitative study showed that death and infection from Lassa fever fell continuously as more and more exposed individuals were detected and isolated for treatment. The study therefore suggested that any measure taken to eradicate or curtail Lassa fever spread should include detection and isolation of the exposed humans for prompt treatments. [ABSTRACT FROM AUTHOR]

Background Omicron has become the mainstream epidemic variant of severe acute respiratory syndrome coronavirus 2 worldwide. One reason for the high infectivity of this variant is its ability to multiply rapidly in the human body. It has been speculated that, in general, the short period required for virus multiplication affects the incubation period and timing of viral shedding that begins during the incubation period. However, it is unclear whether these effects can be related to the Omicron variant. Similar to a recent human challenge study, in this study, patients with known timing of Omicron infection were followed up in a hospital before the onset of the disease. Methods In two patients, the viral shedding was investigated and analysed along with symptoms before and after the disease onset. Results The incubation period for Omicron was 30-36 h; this was shorter than the average incubation period of the alpha variant in the human challenge study and that reported in a systematic review and meta-analysis (3.5 days). Viral shedding at the nasal site began 19-22 h after infection, approximately 10 h before symptom onset. Conclusion The results of this study demonstrated that in some instances with Omicron (BA.5), the time to viral shedding and the time to disease onset were considerably shorter after infection than those previously reported for Omicron and Alpha variants. We showed the importance of early detection of the viral antigen after viral exposure and early isolation initiation to prevent infection spread. [ABSTRACT FROM AUTHOR]

A local COVID-19 outbreak with two community clusters occurred in a large industrial city, Shaoxing, China, in December 2021 after serial interventions were imposed. We aimed to understand the reason by analysing the characteristics of the outbreak and evaluating the effects of phase-adjusted interventions. Publicly available data from 7 December 2021 to 25 January 2022 were collected to analyse the epidemiological characteristics of this outbreak. The incubation period was estimated using Hamiltonian Monte Carlo method. A well-fitted extended susceptible-exposed-infectious-recovered model was used to simulate the impact of different interventions under various combination of scenarios. There were 387 SARS-CoV-2-infected cases identified, and 8.3% of them were initially diagnosed as asymptomatic cases. The estimated incubation period was 5.4 (95% CI 5.2–5.7) days for all patients. Strengthened measures of comprehensive quarantine based on tracing led to less infections and a shorter duration of epidemic. With a same period of incubation, comprehensive quarantine was more effective in containing the transmission than other interventions. Our findings reveal an important role of tracing and comprehensive quarantine in blocking community spread when a cluster occurred. Regions with tense resources can adopt home quarantine as a relatively affordable and low-impact intervention measure compared with centralized quarantine. [ABSTRACT FROM AUTHOR]

The physiological and metabolic response of insects to varied temperature has getting enormous attention in recent times. Insects are poikilothermic organisms; their growth, development, reproduction and survival depend on temperature. The citrus butterflies, Papilio demoleus L. and Papilio polytes L. are two important butterfly pests on citrus crops. The larval stage of pest inflicts economic damage by defoliating large quantity of foliage. The hypothesis that the development of these citrus butterfly species mainly depends upon surrounding temperature was studied under controlled laboratory condition at constant temperature of 23, 28 and 32°C on leaves of acid lime (Citrus aurantifolia Swingle). The results revealed an incubation period of 3.39, 3.06 and 2.82 days respectively, at 23, 28 and 32°C for P. demoleus whereas the incubation period was 3.83, 3.61 and 3.08 days respectively at 23, 28 and 32°C for P. polytes. The larval duration ranged from 11.18 to 16.49 and 13.15 to 14.88 days, respectively for P. demoleus and P. polytes at different temperature regimes. The pupal duration of 8.83 to 17.53 and 8.40 to 13.36 days were observed for P. demoleus and P. polytes respectively. The P. demoleus and P. polytes took 27.83 to 44.67 and 31.78 to 41.47 days respectively, for completion of their entire life cycle. Overall, development of two citrus butterfly species was significantly affected by temperature and temperature was found to be a key factor that influenced the development of these two citrus butterflies on acid lime. [ABSTRACT FROM AUTHOR]

Cowslip (Primula veris subsp. veris) is an important medicinal herb, which produces valuable bioactive compounds including polyphenolic compounds and triterpene saponins, especially in its rhizomes and roots, exhibiting antioxidant, anti-inflammatory, and antimicrobial activities. As a result, the extracts could be exploited by the industry as high-added value food supplements, drugs, and foaming agents. In the present study, the in vitro seed germination potential under different photoperiod regimes and culture periods was assessed (MS solidified medium + 250 mg L−1 GA3 + 20 sucrose g L−1). The results showed higher germination rate (85.29%) and acceleration of maximum germination potential (85 days) under 16 h photoperiod, as compared with 24 h darkness (78.05%, 110 days). Following that, the impacts of eight abiotic elicitors; salicylic acid (SA), casein hydrolysate (CH), L-proline, silver nitrate (AgNO3), cobalt chloride (CoCl2), jasmonic acid (JA), and putrescine, on total phenolics (TPC), flavonoids (TFC), and saponins content, and antioxidant activity on adventitious root cultures, were investigated. After 60 days of liquid culture [MS medium + 5.4 µM α-naphthaleacetic acid (NAA) + 0.5 µM kinetin + 30 g L−1 sucrose] on a continuous rotary shaker (120 rpm, 24 h darkness, 22 °C), TPC was stimulated by 250 µM SA (5.13 mg GAE g−1 DW) or 30 µM AgNO3 (4.75 mg GAE g−1 DW), being 2.06- and 1.91-fold higher than the non-elicited roots. SA at 250 µM obtained significantly greater TFC (2.00 mg RUT g−1 DW) and the strongest antioxidant activity (6.22 mg Trolox g−1 DW) by 2.2-fold, compared to control. The most remarkable augmentation on total saponins was determined under 50 µM JA (113.18 mg oleanolic acid g−1 DW), being 2.35-fold higher than the control. This study constitutes initial documentation for increased accumulation of phenolics, flavonoids, and saponins as strong antioxidants agents in cowslip adventitious roots via an in vitro abiotic elicitation system. Key Message: SA (250 μM) best elicited phenols, flavonoids and antioxidant potential, whereas JA (50 μM) saponins accumulation in adventitious in vitro root liquid cultures of cowslip on a continuous rotary shaker. [ABSTRACT FROM AUTHOR]

Abstract Background After the first COVID-19 wave caused by the ancestral lineage, the pandemic has been fueled from the continuous emergence of new SARS-CoV-2 variants. Understanding key time-to-event periods for each emerging variant of concern is critical as it can provide insights into the future trajectory of the virus and help inform outbreak preparedness and response planning. Here, we aim to examine how the incubation period, serial interval, and generation time have changed from the ancestral SARS-CoV-2 lineage to different variants of concern. Methods We conducted a systematic review and meta-analysis that synthesized the estimates of incubation period, serial interval, and generation time (both realized and intrinsic) for the ancestral lineage, Alpha, Beta, and Omicron variants of SARS-CoV-2. Results Our study included 280 records obtained from 147 household studies, contact tracing studies, or studies where epidemiological links were known. With each emerging variant, we found a progressive shortening of each of the analyzed key time-to-event periods, although we did not find statistically significant differences between the Omicron subvariants. We found that Omicron BA.1 had the shortest pooled estimates for the incubation period (3.49 days, 95% CI: 3.13–4.86 days), Omicron BA.5 for the serial interval (2.37 days, 95% CI: 1.71–3.04 days), and Omicron BA.1 for the realized generation time (2.99 days, 95% CI: 2.48–3.49 days). Only one estimate for the intrinsic generation time was available for Omicron subvariants: 6.84 days (95% CrI: 5.72–8.60 days) for Omicron BA.1. The ancestral lineage had the highest pooled estimates for each investigated key time-to-event period. We also observed shorter pooled estimates for the serial interval compared to the incubation period across the virus lineages. When pooling the estimates across different virus lineages, we found considerable heterogeneities (I 2 > 80%; I 2 refers to the percentage of total variation across studies that is due to heterogeneity rather than chance), possibly resulting from heterogeneities between the different study populations (e.g., deployed interventions, social behavior, demographic characteristics). Conclusions Our study supports the importance of conducting contact tracing and epidemiological investigations to monitor changes in SARS-CoV-2 transmission patterns. Our findings highlight a progressive shortening of the incubation period, serial interval, and generation time, which can lead to epidemics that spread faster, with larger peak incidence, and harder to control. We also consistently found a shorter serial interval than incubation period, suggesting that a key feature of SARS-CoV-2 is the potential for pre-symptomatic transmission. These observations are instrumental to plan for future COVID-19 waves.

Three hybrid populations (F1) of Coffea arabica were evaluated under field and laboratory conditions, derived from sources carrying the SH1 coffee leaf rust (CLR) resistance gene and the CX.2385 line, obtained from the Caturra × Timor Hybrid CIFC-1343. The results obtained under controlled conditions and analyzed using survival curves allowed to estimate the probable times (p < 0.05) for the development of symptoms associated with CLR in the plants of populations evaluated. Phenotypic variation was observed as a defense response to Hemileia vastatrix infection, and plants with incomplete resistance to CLR were identified via an evaluation using the increasing lesions scale. The plants with incomplete resistance exhibited a delay in the development of the incubation period and an absence of the development of the dormancy period. Data suggest that when resistance genes in the sources are defeated by compatible strains, their recombination can give rise to new levels of resistance in the progeny. Additionally, the detached leaf methodology is recommended as an alternative to preselect genotypes with resistance to CLR, thus reducing the number of plants that are finally planted for field evaluations.

Media coverage can greatly impact the spread of infectious diseases. Taking into consideration the impacts of media coverage, we propose an SEIR model with a media coverage mediated nonlinear infection force. For this novel disease model, we identify the basic reproduction number using the next generation matrix method and establish the global threshold results: If the basic reproduction number $ \mathcal{R}_{0} < 1 $, then the disease-free equilibrium $ P_{0} $ is stable, and the disease dies out. If $ \mathcal{R}_{0} > 1 $, then the endemic equilibrium $ P^{*} $ is stable, and the disease persists. Sensitivity analysis indicates that the basic reproduction number $ \mathcal{R}_{0} $ is most sensitive to the population recruitment rate $ \Lambda $ and the disease transmission rate $ \beta _{1} $.

Abstract Background The serial interval is the period of time between symptom onset in the primary case and symptom onset in the secondary case. Understanding the serial interval is important for determining transmission dynamics of infectious diseases like COVID-19, including the reproduction number and secondary attack rates, which could influence control measures. Early meta-analyses of COVID-19 reported serial intervals of 5.2 days (95% CI: 4.9–5.5) for the original wild-type variant and 5.2 days (95% CI: 4.87–5.47) for Alpha variant. The serial interval has been shown to decrease over the course of an epidemic for other respiratory diseases, which may be due to accumulating viral mutations and implementation of more effective nonpharmaceutical interventions. We therefore aggregated the literature to estimate serial intervals for Delta and Omicron variants. Methods This study followed Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. A systematic literature search was conducted of PubMed, Scopus, Cochrane Library, ScienceDirect, and preprint server medRxiv for articles published from April 4, 2021, through May 23, 2023. Search terms were: (“serial interval” or “generation time”), (“Omicron” or “Delta”), and (“SARS-CoV-2” or “COVID-19”). Meta-analyses were done for Delta and Omicron variants using a restricted maximum-likelihood estimator model with a random effect for each study. Pooled average estimates and 95% confidence intervals (95% CI) are reported. Results There were 46,648 primary/secondary case pairs included for the meta-analysis of Delta and 18,324 for Omicron. Mean serial interval for included studies ranged from 2.3–5.8 days for Delta and 2.1–4.8 days for Omicron. The pooled mean serial interval for Delta was 3.9 days (95% CI: 3.4–4.3) (20 studies) and Omicron was 3.2 days (95% CI: 2.9–3.5) (20 studies). Mean estimated serial interval for BA.1 was 3.3 days (95% CI: 2.8–3.7) (11 studies), BA.2 was 2.9 days (95% CI: 2.7–3.1) (six studies), and BA.5 was 2.3 days (95% CI: 1.6–3.1) (three studies). Conclusions Serial interval estimates for Delta and Omicron were shorter than ancestral SARS-CoV-2 variants. More recent Omicron subvariants had even shorter serial intervals suggesting serial intervals may be shortening over time. This suggests more rapid transmission from one generation of cases to the next, consistent with the observed faster growth dynamic of these variants compared to their ancestors. Additional changes to the serial interval may occur as SARS-CoV-2 continues to circulate and evolve. Changes to population immunity (due to infection and/or vaccination) may further modify it.

The severe shortfall in testing supplies during the initial COVID-19 outbreak and ensuing struggle to manage the pandemic have affirmed the critical importance of optimal supply-constrained resource allocation strategies for controlling novel disease epidemics. To address the challenge of constrained resource optimization for managing diseases with complications like pre- and asymptomatic transmission, we develop an integro partial differential equation compartmental disease model which incorporates realistic latent, incubation, and infectious period distributions along with limited testing supplies for identifying and quarantining infected individuals. Our model overcomes the limitations of typical ordinary differential equation compartmental models by decoupling symptom status from model compartments to allow a more realistic representation of symptom onset and presymptomatic transmission. To analyze the influence of these realistic features on disease controllability, we find optimal strategies for reducing total infection sizes that allocate limited testing resources between ‘clinical’ testing, which targets symptomatic individuals, and ‘non-clinical’ testing, which targets non-symptomatic individuals. We apply our model not only to the original, delta, and omicron COVID-19 variants, but also to generically parameterized disease systems with varying mismatches between latent and incubation period distributions, which permit varying degrees of presymptomatic transmission or symptom onset before infectiousness. We find that factors that decrease controllability generally call for reduced levels of non-clinical testing in optimal strategies, while the relationship between incubation-latent mismatch, controllability, and optimal strategies is complicated. In particular, though greater degrees of presymptomatic transmission reduce disease controllability, they may increase or decrease the role of non-clinical testing in optimal strategies depending on other disease factors like transmissibility and latent period length. Importantly, our model allows a spectrum of diseases to be compared within a consistent framework such that lessons learned from COVID-19 can be transferred to resource constrained scenarios in future emerging epidemics and analyzed for optimality.

Sporadic Creutzfeldt-Jakob disease (sCJD), the most common human prion disease, is thought to occur when the cellular prion protein (PrPC) spontaneously misfolds and assembles into prion fibrils, culminating in fatal neurodegeneration. In a genome-wide association study of sCJD, we recently identified risk variants in and around the gene STX6, with evidence to suggest a causal increase of STX6 expression in disease-relevant brain regions. STX6 encodes syntaxin-6, a SNARE protein primarily involved in early endosome to trans-Golgi network retrograde transport. Here we developed and characterised a mouse model with genetic depletion of Stx6 and investigated a causal role of Stx6 expression in mouse prion disease through a classical prion transmission study, assessing the impact of homozygous and heterozygous syntaxin-6 knockout on disease incubation periods and prion-related neuropathology. Following inoculation with RML prions, incubation periods in Stx6−/− and Stx6+/− mice differed by 12 days relative to wildtype. Similarly, in Stx6−/− mice, disease incubation periods following inoculation with ME7 prions also differed by 12 days. Histopathological analysis revealed a modest increase in astrogliosis in ME7-inoculated Stx6−/− animals and a variable effect of Stx6 expression on microglia activation, however no differences in neuronal loss, spongiform change or PrP deposition were observed at endpoint. Importantly, Stx6−/− mice are viable and fertile with no gross impairments on a range of neurological, biochemical, histological and skeletal structure tests. Our results provide some support for a pathological role of Stx6 expression in prion disease, which warrants further investigation in the context of prion disease but also other neurodegenerative diseases considering syntaxin-6 appears to have pleiotropic risk effects in progressive supranuclear palsy and Alzheimer's disease.

Background: Pre‐transfusion testing (PTT) encompasses a set of mandatory laboratory tests performed before red blood cell transfusion. The antibody screen, one component of PTT, commonly includes a 10–20 min incubation. The primary aim of this study was to determine if this period can be reduced when using current immunohematology methodologies. Methods and Materials: Antibody screens were performed on reagent samples using Glass or Gel‐based column agglutination technologies (CAT) and a solid phase red cell adherence (SPRCA) assay, with incubation periods of 1, 5, 10 and 15 min, and 20 min (SPRCA assay only). For each method, the shortest period producing a minimum of a 1+ reaction with all reagent samples was considered optimal. The sensitivity of each assay using the optimal period was calculated after performing antibody screens on 100 patient samples. Results and Discussion: It was demonstrated that the incubation period in the SPRCA and Glass CAT systems can be reduced to 5 and 10 min, respectively, while achieving high assay sensitivity (98.9% in both). The incubation period in the Gel CAT system cannot be reduced from 15 min. Significant association between titre and reaction strength was observed for all three screening methods (p < 0.001 for both CAT methods, p = 0.041 for SPRCA). This study demonstrates that the incubation period used in the antibody screen can be reduced when using systems employing the Glass CAT and SPRCA methods, without affecting assay sensitivity. If confirmed, it could result in faster completion of PTT. [ABSTRACT FROM AUTHOR]

Purpose: The worldwide mpox outbreak starting in May 2022 marks the occurrence of another previously atypical infectious disease in Europe. This study's objective was to present a comprehensive overview based on the gathered data and to illustrate the approach of the Cologne Health Department to contain the mpox outbreak. Methods: In this retrospective observational study, 368 individuals reported to the Cologne Health Department as PCR-positive for mpox were included. Data were collected in structured telephone interviews and digitally processed. Results: The first mpox case in Cologne was recorded on May 24, 2022. The local outbreak lasted approximately 4 months and reached its peak in July. The last reported case in Cologne occurred on September 17. Transmissions mostly occurred through sexual contacts (67.4%) or other close physical contacts (4.6%) between men, but also through fomites, in the context of events or occasionally in the work environment. In 21.5% of cases, no route of infection could be determined. The mean incubation period was 8.2 days. Clinically, mpox infections usually presented with skin and/or mucosal lesions accompanied by general symptoms. In 74.8% of cases, a prodromal stage was absent. Initially, the rash often had an unspecific appearance, but in the further clinical course, it usually passed through the typical stages. Most infections resolved spontaneously under home care. In 3.5% of cases, however, inpatient hospitalisation was required. Infected persons with a previous smallpox vaccination had 0.43 times the odds of unvaccinated persons to be affected by lesions in 3 or more body regions and 0.30 times the odds to develop lesions in all 5 body regions. Previous vaccination statistically reduced the total duration of symptoms by 2.0 days. Conclusions: The mpox outbreak 2022 in Cologne primarily affected men who have sex with men and have reported recent sexual encounters. The observed average incubation period was shorter than initially assumed. Mucosal involvement and associated symptoms occur in a relevant number of cases and can lead to more severe clinical courses. Previous smallpox vaccination was statistically significantly associated with milder courses of mpox. In the case of an unclear rash or symptoms suggesting mucosal involvement, mpox should be considered as a differential diagnosis. An equally rapid and well-orchestrated public health response are crucial for infection control. [ABSTRACT FROM AUTHOR]

Background: After the first COVID-19 wave caused by the ancestral lineage, the pandemic has been fueled from the continuous emergence of new SARS-CoV-2 variants. Understanding key time-to-event periods for each emerging variant of concern is critical as it can provide insights into the future trajectory of the virus and help inform outbreak preparedness and response planning. Here, we aim to examine how the incubation period, serial interval, and generation time have changed from the ancestral SARS-CoV-2 lineage to different variants of concern. Methods: We conducted a systematic review and meta-analysis that synthesized the estimates of incubation period, serial interval, and generation time (both realized and intrinsic) for the ancestral lineage, Alpha, Beta, and Omicron variants of SARS-CoV-2. Results: Our study included 280 records obtained from 147 household studies, contact tracing studies, or studies where epidemiological links were known. With each emerging variant, we found a progressive shortening of each of the analyzed key time-to-event periods, although we did not find statistically significant differences between the Omicron subvariants. We found that Omicron BA.1 had the shortest pooled estimates for the incubation period (3.49 days, 95% CI: 3.13–4.86 days), Omicron BA.5 for the serial interval (2.37 days, 95% CI: 1.71–3.04 days), and Omicron BA.1 for the realized generation time (2.99 days, 95% CI: 2.48–3.49 days). Only one estimate for the intrinsic generation time was available for Omicron subvariants: 6.84 days (95% CrI: 5.72–8.60 days) for Omicron BA.1. The ancestral lineage had the highest pooled estimates for each investigated key time-to-event period. We also observed shorter pooled estimates for the serial interval compared to the incubation period across the virus lineages. When pooling the estimates across different virus lineages, we found considerable heterogeneities (I2 > 80%; I2 refers to the percentage of total variation across studies that is due to heterogeneity rather than chance), possibly resulting from heterogeneities between the different study populations (e.g., deployed interventions, social behavior, demographic characteristics). Conclusions: Our study supports the importance of conducting contact tracing and epidemiological investigations to monitor changes in SARS-CoV-2 transmission patterns. Our findings highlight a progressive shortening of the incubation period, serial interval, and generation time, which can lead to epidemics that spread faster, with larger peak incidence, and harder to control. We also consistently found a shorter serial interval than incubation period, suggesting that a key feature of SARS-CoV-2 is the potential for pre-symptomatic transmission. These observations are instrumental to plan for future COVID-19 waves. [ABSTRACT FROM AUTHOR]

Gyps species declined rapidly between the late 1990s and early 2000s in southern Asia due to the use of diclofenac and are listed as Critically Endangered species. Long-term data on breeding ecology is essential to understand the population trends of these threatened species. This study assessed the breeding phenology and reproductive performance of two critically endangered Gyps species--Longbilled Gyps indicus (Scopoli) (LBV) and White-rumped Gyps bengalensis (Gmelin) (WRV) vultures--through long-term monitoring at breeding colonies in Kaghaznagar and Sironcha Forest Divisions in the Deccan Plateau of India between 2010 and 2021. LBV began their nest construction and copulation in the second week of October, and ended in the fourth week of November, while the WRV completed the same between the first and second weeks of October. LBV started egg-laying during the first week of December and ended in the first week of January, with a peak during the third week on 14 December, and the mean incubation period was 54 ± 1 days. The WRV completed their egg-laying early, during the second and third weeks of October, and peaked during the second week on 14 October and had a relatively longer incubation of 61 ± 1 days. For LBV, hatching peaked during the first week of February, and the mean nestling period was 103±2 days, while for WRV hatching peaked much earlier, during the third week of December and the mean nestling period was 105±1 days. Overall nest success, breeding success, and productivity estimated based on 159 breeding pairs of LBV observed over 12 years were lower compared to that of 124 breeding pairs of WRV observed over 6-year period. The decline in breeding success of LBV since 2019 is discussed in light of cattle poisoning reported in 2018, and the reopening of the Sirpur paper industry (Kaghaznagar) in 2017 that discharges its hazardous effluent into the Peddavagu stream. Therefore, the present study suggests long-term monitoring of breeding colonies including evaluation of the drivers of population and breeding, molecular and toxicological studies, and implementation of Vulture Safe Zones to save these critically endangered Gyps vultures from local extinction. [ABSTRACT FROM AUTHOR]

We compared serial intervals and incubation periods for SARS-CoV-2 Omicron BA.1 and BA.2 subvariants and Delta variants in Singapore. Median incubation period was 3 days for BA.1 versus 4 days for Delta. Serial interval was 2 days for BA.1 and 3 days for BA.2 but 4 days for Delta.