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BackgroundThe COVID-19 pandemic had a severe impact globally, yet African populations exhibited unexpectedly lower rates of severe disease and mortality. We investigated the potential role of pre-existing immunity in shaping the epidemiology of COVID-19 in Africa.MethodsPlasma collected from Senegalese female sex workers prior to the COVID-19 pandemic was screened for SARS-CoV-2 and human coronavirus (hCoV) antibodies by virion immunoblots. For antibody-reactive plasma, paired peripheral blood mononuclear cells were stimulated by fusion proteins and IFN-γ cellular responses were assessed via ELISPOT.ResultsWe observed substantial levels of pre-existing cross-reactive immunity to SARS-CoV-2, stemming from prior exposure to seasonal hCoVs. Our antibody analysis revealed a 23.5% (47/200) seroprevalence rate against SARS-CoV-2 nucleocapsid (N). These samples were then probed for antibodies against hCoV spike (S) and/or N antigens; 85.1% (40/47), 70.2% (33/47), and 95.7% (45/47) were antibody reactive against hCoV-229E, hCoV-OC43, or hCoV-HKU1, respectively. Our analysis of cellular responses also demonstrated cross-reactivity to SARS-CoV-2 with 80.0% (36/45) and 82.2% (37/45) showing IFN-γ responses against S and N, respectively. A unique pre-pandemic subject had cross-reactive SARS-CoV-2 S antibodies with detectable neutralization and cross-reactive cellular responses.ConclusionThese findings suggest that prior hCoV exposure may induce cross-reactive adaptive immunity, potentially contributing to protection against COVID-19. Our study provides unique data on the dynamics of hCoV and SARS-CoV-2 immunity in Senegal and underscores the importance of understanding the role of pre-existing immunity in shaping COVID-19 outcomes globally.

Background: Early evidence suggested that the impact of the COVID-19 pandemic was less severe in Africa compared to other parts of the world. However, more recent studies indicate higher SARS-CoV-2 infection and COVID-19 mortality rates on the continent than previously documented. Research is needed to better understand SARS-CoV-2 infection and immunity in Africa. Methods: In early 2021, we studied the immune responses in healthcare workers (HCWs) at Lagos University Teaching Hospital (n = 134) and Oxford-AstraZeneca COVID-19 vaccine recipients from the general population (n = 116) across five local government areas (LGAs) in Lagos State, Nigeria. Western blots were used to simultaneously detect SARS-CoV-2 spike and nucleocapsid (N) antibodies (n = 250), and stimulation of peripheral blood mononuclear cells with N followed by an IFN-γ ELISA was used to examine T cell responses (n = 114). Results: Antibody data demonstrated high SARS-CoV-2 seroprevalence of 72·4% (97/134) in HCWs and 60·3% (70/116) in the general population. Antibodies directed to only SARS-CoV-2 N, suggesting pre-existing coronavirus immunity, were seen in 9·7% (13/134) of HCWs and 15·5% (18/116) of the general population. T cell responses against SARS-CoV-2 N (n = 114) were robust in detecting exposure to the virus, demonstrating 87·5% sensitivity and 92·9% specificity in a subset of control samples tested. T cell responses against SARS-CoV-2 N were also observed in 83.3% of individuals with N-only antibodies, further suggesting that prior non-SARS-CoV-2 coronavirus infection may provide cellular immunity to SARS-CoV-2. Conclusions: These results have important implications for understanding the paradoxically high SARS-CoV-2 infection with low mortality rate in Africa and supports the need to better understand the implications of SARS-CoV-2 cellular immunity.

Abstract Background The Joint United Nations Programme on HIV/AIDS 90–90-90 goal envisions 90% of all people receiving antiretroviral therapy to be virally suppressed by 2020. Implied in that goal is that viral load be quantified for all patients receiving treatment, which is a challenging undertaking given the complexity and high cost of standard-of-care viral load testing methods. Recently developed point-of-care viral load testing devices offer new promise to improve access to viral load testing by bringing the test closer to the patient and also returning results faster, often same-day. While manufactures have evaluated point-of-care assays using reference panels, empiric data examining the impact of the new technology against standard-of-care monitoring in low- and middle-income settings are lacking. Our goal in this trial is to compare a point-of-care to standard-of-care viral load test on impact on various clinical outcomes as well to assess the acceptability and feasibility of using the assay in a resource-limited setting. Methods Using a two-arm randomized control trial design, we will enroll 794 patients from two different HIV treatment sites in Nigeria. Patients will be randomized 1:1 for point-of-care or standard-of-care viral load monitoring (397 patients per arm). Following initiation of treatment, viral load will be monitored at patients’ 6- and 12-month follow-up visits using either point-of-care or standard-of-care testing methods, based on trial assignment. The monitoring schedule will follow national treatment guidelines. The primary outcome measure in this trial is proportion of patients with viral suppression at month 12 post-initiation of treatment. The secondary outcome measures encompass acceptability, feasibility, and virologic impact variables. Discussion This clinical trial will provide information on the impact of using point-of-care versus standard-of-care viral load testing on patient clinical outcomes; the study will also supply data on the acceptability and feasibility of point-of-care viral load monitoring in a resource-limited setting. If this method of testing is acceptable and feasible, and also superior to standard of care, the results of the trial and the information gathered will inform future scaled implementation and further optimization of the clinic-laboratory network that is critical for monitoring achievement of the 90–90-90 goals. Trial registration US National Institutes of Health Clinical Trials.gov: NCT03533868. Date of Registration: 23 May 2018. Protocol Version: 10. Protocol Date: 30 March 2018.

Objectives: Chikungunya virus (CHIKV), a reemerging global public health concern, which causes acute febrile illness, rash, and arthralgia and may affect both mothers and infants during pregnancy. Mother-to-child transmission (MTCT) of CHIKV in Africa remains understudied. Methods: Our cohort study screened 1006 pregnant women with a Zika/dengue/CHIKV rapid test at two clinics in Nigeria between 2019 and 2022. Women who tested positive for the rapid test were followed through their pregnancy and their infants were observed for 6 months, with a subset tested by reverse transcription-polymerase chain reaction (RT-PCR) and neutralization, to investigate seropositivity rates and MTCT of CHIKV. Results: Of the 1006, 119 tested positive for CHIKV immunoglobulin (Ig)M, of which 36 underwent detailed laboratory tests. While none of the IgM reactive samples were RT-PCR positive, 14 symptomatic pregnant women were confirmed by CHIKV neutralization test. Twelve babies were followed with eight normal and four abnormal outcomes, including stillbirth, cleft lip/palate with microcephaly, preterm delivery, polydactyly with sepsis, and jaundice. CHIKV IgM testing identified three possible antepartum transmissions. Conclusion: In Nigeria, we found significant CHIKV infection in pregnancy and possible CHIKV antepartum transmission associated with birth abnormalities.

Abstract Social media plays an outsized role in information dissemination, issue mobilization, and public influence. For environmental nongovernmental organizations (“eNGOs”), social media plays a critical role in fundraising and inspiring engaged audiences using rich media and punchy taglines. Yet, there is little to no accounting of whether and how eNGOs have adopted social media, limiting analyses of how eNGOs are leveraging social media to develop effective communication strategies and campaigns. We analyzed the social media presence of over 100 eNGOs. We evaluated which platforms are used by eNGOs and differences between them in terms of their visibility on social media. 88%–97% of the eNGOs in our sample use four out of the five leading social media platforms. There were marked differences across eNGOs and platforms in terms of public visibility, represented by the number of followers. eNGOs focusing on advocacy, aquatic environments, and species conservation had significantly larger numbers of followers. Our findings indicate that conservation can make more headway on newer, more visually‐oriented platforms that also have stronger youth traction. We use our analyses to identify which eNGOs have much larger followings on social media than expected. These leaders can provide lessons on how eNGOs can enhance their social media impact.

Abstract Coffee is a major tropical commodity crop that can provide supplementary habitat for native wildlife. In Asia, coffee production is an increasingly important driver of landscape transformation and shifts between different coffee species is a major dimension of agroforestry trends. Yet few studies have compared the ecological impacts of conversion between different coffee species. We evaluated whether or not the two species of coffee grown globally—Coffea arabica and C. canephora (denoted “robusta”)—had equivalent avian conservation value in the Western Ghats, India, where robusta production has become increasingly dominant. We found that habitat specialist and functional guild diversity was higher in arabica, and that arabica was more profitable. However, robusta farms generally supported the same or slightly higher abundances of habitat specialists and functional guilds, largely due to dense canopy and landscape-level forest cover. Farming practices, chiefly pesticide use, may affect the suitability of coffee agroforests as habitat for avian specialists, and at present, robusta farmers tended to use less pesticide. Given future projections for arabica to robusta conversion in tropical Asia, our study indicates that certification efforts should prioritize maintaining native canopy shade trees and forest cover to ensure that coffee landscapes can continue providing biodiversity benefits.

Ebola virus (EBOV) caused more than 11,000 deaths during the 2013-2016 epidemic in West Africa without approved vaccines or immunotherapeutics. Despite its high lethality in some individuals, EBOV infection can produce little to no symptoms in others. A better understanding of the immune responses in individuals who experienced minimally symptomatic and asymptomatic infection could aid the development of more effective vaccines and antivirals against EBOV and related filoviruses.Between August and November 2017, blood samples were collected from 19 study participants in Lagos, Nigeria, including 3 Ebola virus disease (EVD) survivors, 10 individuals with documented close contact with symptomatic EVD patients, and 6 control healthcare workers for a cross-sectional serosurvey and T cell analysis. The Lagos samples, as well as archived serum collected from healthy individuals living in surrounding areas of the 1976 Democratic Republic of Congo (DRC) epidemic, were tested for EBOV IgG using commercial enzyme-linked immunosorbent assays (ELISAs) and Western blots. We detected antibodies in 3 out of 3 Lagos survivors and identified 2 seropositive individuals not known to have ever been infected. Of the DRC samples tested, we detected antibodies in 9 out of 71 (12.7%). To characterize the T cell responses in the Lagos samples, we developed an anthrax toxin-based enzyme-linked immunospot (ELISPOT) assay. The seropositive asymptomatic individuals had T cell responses against EBOV nucleoprotein, matrix protein, and glycoprotein 1 that were stronger in magnitude compared to the survivors.Our data provide further evidence of EBOV exposure in individuals without EVD-like illness and, for the first time, demonstrate that these individuals have T cell responses that are stronger in magnitude compared to severe cases. These findings suggest that T cell immunity may protect against severe EVD, which has important implications for vaccine development.

While there has been a rapid global scale-up of antiretroviral therapy programs over the past decade, there are limited data on long-term outcomes from large cohorts in resource-constrained settings. Our objective in this evaluation was to measure multiple outcomes during first-line antiretroviral therapy in a large treatment program in Nigeria.We conducted a retrospective multi-site program evaluation of adult patients (age ≥15 years) initiating antiretroviral therapy between June 2004 and February 2012 in Nigeria. The baseline characteristics of patients were described and longitudinal analyses using primary endpoints of immunologic recovery, virologic rebound, treatment failure and long-term adherence patterns were conducted.Of 70,002 patients, 65.2% were female and median age was 35 (IQR: 29-41) years; 54.7% were started on a zidovudine-containing and 40% on a tenofovir-containing first-line regimen. Median CD4+ cell counts for the cohort started at 149 cells/mm3 (IQR: 78-220) and increased over duration of ART. Of the 70,002 patients, 1.8% were reported as having died, 30.1% were lost to follow-up, and 0.1% withdrew from treatment. Overall, of those patients retained and with viral load data, 85.4% achieved viral suppression, with 69.3% achieving suppression by month 6. Of 30,792 patients evaluated for virologic failure, 24.4% met criteria for failure and of 45,130 evaluated for immunologic failure, 34.0% met criteria for immunologic failure, with immunologic criteria poorly predicting virologic failure. In adjusted analyses, older age, ART regimen, lower CD4+ cell count, higher viral load, and inadequate adherence were all predictors of virologic failure. Predictors of immunologic failure differed slightly, with age no longer predictive, but female sex as protective; additionally, higher baseline CD4+ cell count was also predictive of failure. Evaluation of long-term adherence patterns revealed that the majority of patients retained through 84 months maintained ≥95% adherence.While improved access to HIV care and treatment remains a challenge in Nigeria, our study shows that a high quality of care was achieved as evidenced by strong long-term clinical, immunologic and virologic outcomes.

The Amazon basin is one of the most biologically diverse places on earth. However, agricultural expansion and infrastructure development have led to widespread deforestation that threatens the survival of many taxa. Conservation strategies to contest these threats include protected areas and environmental legislation. Nevertheless, the basic biology of many taxa is largely unknown, which poses an immense challenge when devising effective strategies to safeguard such species in the long-term. This is particularly true for primates. Monkeys from the genus Mico are poorly studied with half of the currently known species being described after 1976, and their distribution and threats remain poorly understood. Using the model Maxent, we re-evaluated the distribution range for Rondon’s marmoset, one of the most threatened species in this genus. Our results estimated a distribution that is 15,500 km2 smaller than previously described for this species (68,649 km2). Furthermore, much of its modeled distribution (71%) lies outside of protected areas. Agriculture expansion and infrastructure development have converted/destroyed 20,532 km2 of forest within its range (38%) mainly in areas without protection. Another 10,316 km2 of forest is projected to be cleared by 2040 under current deforestation patterns. The expected cumulative loss of over 50% of its range size in the coming 15 years raise awareness about the threaten category of this species. In the absence of new protected areas, it remains to be seen whether Rondon’s marmoset can be effectively conserved in remaining fragments of forest in farmlands.