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Vaccinating dogs against rabies is an effective means of reducing human rabies. We subjected 1327 clinically diagnosed human rabies death and mass dog vaccination (MDV) data during 2006–2018 to quantify the impacts of MDV on human rabies incidence in Bangladesh and a subset of rabies death data (422) for clinico-epidemiological analysis. A positive and increasing trend of MDV (p = 0.01 and tau = 0.71) and a negative and declining trend (p

We herein report the first case of Mediterranean glucose-6-phosphate dehydrogenase (G6PD) variant from Bangladesh. A boy had been admitted to hospital and was diagnosed with uncomplicated Plasmodium vivax infection and treated with 30 mg/kg body weight (BW) chloroquine for 3 days and 4.8 mg/kg BW primaquine (PQ) to be taken over 14 days. The boy was discharged but represented 4 days later with severe hemoglobinuria and fatigue. Hemoglobin was measured at 6.0 g/dL and serum bilirubin was at 5.6 mg/dL, although malaria microscopy was negative. The boy had taken the 4-fold recommended daily dose of PQ and was treated with two fresh blood transfusions. Subsequent molecular analysis showed the boy to have the Mediterranean G6PD variant and a G6PD activity of 0.93 U/gHb.

Community awareness regarding rabies and treatment seeking behaviours are critical both for the prevention and control of the disease in human and animals. We conducted a study to explore people's awareness about rabies, their attitudes towards dogs and practices associated with treating dog bites in Satkhira Sadar, a south‐western sub‐district of Bangladesh. Of the total 3200 households (HHs) surveyed, the majority of the respondents have heard about rabies (73%) and there was a high level of awareness that dog bite is the main cause of rabies (86%), and that rabies can be prevented by vaccination (85%). However, 59% of the dog bite victims first seek treatment from traditional healers instead of visiting the hospitals, 29% received the rabies vaccine, 2% practiced proper wound washing with soap and water, while 4.8% have not taken any measures. None of the victims have received rabies immunoglobulin (RIG). Of the respondents, 5.2% reported a history of dog bite in at least one family member, and 11.8% reported a history of dog bite in domestic animals during the previous year. The HHs having a higher number of family members (OR: 1.13, 95% CI: 1.07–1.2), having a pet dog (OR: 2.1, 95% CI: 1.4–3.2) and caring or feeding a community dog (OR: 2.1, 95% CI: 1.4–2.9) showed an increased risk of getting a dog bite. Among the bite victims, 3.6% (n = 6) humans and 15.8% (n = 60) animals died. As a measure for dog population management (DPM), 56% preferred sterilization while the rest preferred killing of dogs. The current treatment seeking behaviours of the respondents should be improved through additional education and awareness programme and better availability for the provision of post‐exposure prophylaxis in Bangladesh. We recommend scaling up national mass dog vaccination and DPM to reduce the burden of rabies cases and dog bites in Bangladesh.

Globally, Bangladesh ranks third in the number of human deaths from rabies. Although dogs are the principal known transmitters of rabies and knowledge of dog populations is essential for effective national control and proper planning, dog control programs are scarce in Bangladesh. Our objective was to count dogs in a rural area to understand the dog population of the country. For this purpose we selected six unions of Raipura upazila in Narsingdi district. Dog counting was done by direct observation following accepted guidelines. We determined the mean density of the dog population in Bangladesh to be 14 dog/km 2 (95% CI 3.7, 24) and the human:dog ratio to be 120 (95% CI 55, 184). Our paper contribute to the literature which shows great variation in the human:dog ratio across regions of the developing world. The human:dog ratio depends on the area's human (as well as dog) population, whereas dog density per unit area indicates the true number of dogs. We propose that extrapolating from the human:dog ratios of other regions not be relied upon for estimating dog populations, unless the ratios can be supplemented by actual counts of dogs within the target area.

The emergence and spread of artemisinin-resistant Plasmodium falciparum is of huge concern for the global effort toward malaria control and elimination. Artemisinin resistance, defined as a delayed time to parasite clearance following administration of artemisinin, is associated with mutations in the Pfkelch13 gene of resistant parasites. To date, as many as 60 nonsynonymous mutations have been identified in this gene, but whether these mutations have been selected by artemisinin usage or merely reflect natural polymorphism independent of selection is currently unknown. To clarify this, we sequenced the Pfkelch13 propeller domain in 581 isolates collected before (420 isolates) and after (161 isolates) the implementation of artemisinin combination therapies (ACTs), from various regions of endemicity worldwide. Nonsynonymous mutations were observed in 1% of parasites isolated prior to the introduction of ACTs. Frequencies of mutant isolates, nucleotide diversity, and haplotype diversity were significantly higher in the parasites isolated from populations exposed to artemisinin than in those from populations that had not been exposed to the drug. In the artemisinin-exposed population, a significant excess of dN compared to dS was observed, suggesting the presence of positive selection. In contrast, pairwise comparison of dN and dS and the McDonald and Kreitman test indicate that purifying selection acts on the Pfkelch13 propeller domain in populations not exposed to ACTs. These population genetic analyses reveal a low baseline of Pfkelch13 polymorphism, probably due to purifying selection in the absence of artemisinin selection. In contrast, various Pfkelch13 mutations have been selected under artemisinin pressure.

Recent reports on the decline of the efficacy of artemisinin-based combination therapies (ACTs) indicate a serious threat to malaria control. The endoplasmic/sarcoplasmic reticulum Ca 2+ -ATPase ortholog of Plasmodium falciparum (PfSERCA) has been suggested to be the target of artemisinin and its derivatives. It is assumed that continuous artemisinin pressure will affect polymorphism of the PfSERCA gene ( serca ) if the protein is the target. Here, we investigated the polymorphism of serca in parasite populations unexposed to ACTs to obtain baseline information for the study of potential artemisinin-driven selection of resistant parasites. Analysis of 656 full-length sequences from 13 parasite populations in Africa, Asia, Oceania, and South America revealed 64 single nucleotide polymorphisms (SNPs), of which 43 were newly identified and 38 resulted in amino acid substitutions. No isolates showed L263E and S769N substitutions, which were reportedly associated with artemisinin resistance. Among the four continents, the number of SNPs was highest in Africa. In Africa, Asia, and Oceania, common SNPs, or those with a minor allele frequency of ≥0.05, were less prevalent, with most SNPs noted to be continent specific, whereas in South America, common SNPs were highly prevalent and often shared with those in Africa. Of 50 amino acid haplotypes observed, only one haplotype (3D7 sequence) was seen in all four continents (64%). Forty-eight haplotypes had frequencies of less than 5%, and 40 haplotypes were continent specific. The geographical difference in the diversity and distribution of serca SNPs and haplotypes lays the groundwork for assessing whether some artemisinin resistance-associated mutations and haplotypes are selected by ACTs.

In Bangladesh, despite the official introduction of artemisinin combination therapy in 2004, chloroquine+sulfadoxine/pyrimethamine has been used for the treatment of uncomplicated malaria. To assess the distribution of pfcrt, pfmdr1, dhfr, and dhps genotypes in Plasmodium falciparum, we conducted hospital- and community-based surveys in Bandarban, Bangladesh (near the border with Myanmar) in 2007 and 2008. Using nested PCR followed by digestion, 139 P. falciparum isolates were genotyped. We found fixation of a mutation at position 76 in pfcrt and low prevalence of a mutation at position 86 in pfmdr1. In dhfr, the highest pyrimethamine resistant genotype quadruple mutant was found in 19% of isolates, which is significantly higher prevalence than reported in a previous study in Khagrachari (1%) in 2002. Microsatellite haplotypes flanking dhfr of the quadruple mutants in Bangladesh were identical or very similar to those found in Thailand and Cambodia, indicating a common origin for the mutant in these countries. These observations suggest that the higher prevalence of the dhfr quadruple mutant in Bandarban is because of parasite migration from Myanmar. However, continuous use of sulfadoxine/pyrimethamine would have also played a role through selection for the dhfr quadruple mutant. These results indicate an urgent need to collect molecular epidemiological information regarding dhfr and dhps genes, and a review of current sulfadoxine/pyrimethamine usage with the aim of avoiding the widespread distribution of high levels of resistant parasites in Bangladesh.

In recent clinical trials acithromycin in combination with artemisinin derivatives proved to be a promising combination therapy with indifferent to synergistic interaction. The aim of the present study was the assessment of optimal combination ratios for dihydroartemisinin and azithromycin for the treatment of uncomplicated falciparum malaria. The study was conducted in Bandarban, in Southeastern Bangladesh. Plasmodium falciparum isolates collected as part of a clinical trial were cultured for 72 hours. Samples were analyzed using the HRP2 drug sensitivity assay in fixed combinations and checkerboard assays. An indifferent mode of interaction was found for the 1:500 combination of dihydroartemisinine and azithromycin. The sum fractional inhibitory concentrations (SFICs) at IC95 ranged from 0.89 to 1.16 for combination ratios of 1:500 and 1:5000, respectively. A trend towards lower SFICs was observed with rising inhibitory concentrations (i.e. at IC90 and IC95). Correlation analysis suggests a different mode of action for azithromycin as compared to traditional antimalarials.

The combination of artemether and lumefantrine was introduced in 2005 as the official first line therapy for uncomplicated falciparum malaria in Bangladesh. Fresh P. falciparum samples from patients with acute uncomplicated falciparum malaria who presented to the field site at the Bandarban Sadar Hospital in Bangladesh were tested in checkerboard in vitro drug sensitivity assays to assess the interaction between dihydroartemisinin (DHA) and lumefantrine (LUM). Clearly synergistic interactions with an overall mean FIC(50) of 0.52 and individual mean FICs between 0.26 and 0.85 were found. Lowest FICs were 0.41, 0.18, 0.22, 0.15 and 0.11 at different combination ratios. The optimal combination ratio of the drug combination indicated by the lowest mean FIC average was found to be 1:150 DHA:LUM. Although activity correlations between DHA and lumefantrine were significant, indicating possible cross sensitivity patterns, our data confirm that artemether-lumefantrine is a highly synergistic drug combination.