Transactions of The Royal Society of Tropical Medicine and Hygiene最新文献

Background: Focused efforts of the visceral leishmaniasis elimination program have led to a drastic decline in cases, and the present challenge is disease monitoring, which this study aimed to assess.

Methods: A Leishmania kinetoplastid-targeted qPCR quantified parasite load at disease presentation, and following treatment completion (n=49); an additional 80 cases were monitored after completion of treatment.

Results: The parasite load at disease presentation was 13 461.00 (2560.00-37764.00)/µg gDNA, which upon completion of treatment reduced in 47 of 49 cases to 1(1-1)/µg gDNA, p<0.0001. In 80 cases that presented >2 months post-treatment, their parasite burden similarly decreased to 1(1-1)/µg gDNA except in 6 of 80 cases, which were qPCR positive.

Conclusion: In 129 cases of visceral leishmaniasis, qPCR by quantification of parasite burden proved effective for monitoring treatment.

Background: Mosquito-borne diseases pose a significant global public health threat, with Malaysia's Klang Valley experiencing numerous outbreaks in densely populated urban areas.

Methods: This study aimed to estimate the seroprevalence of anti-dengue and anti-chikungunya antibodies among urban refugees in the Klang Valley, Malaysia, and identify associated risk factors.

Results: High seroprevalence of anti-dengue immunoglobulin G (IgG) and IgM (60.0% [confidence interval {CI} 55.39 to 64.48] and 9.2% [CI 6.77 to 12.25], respectively) were observed among refugees >18 years of age (χ22=11.720, p=0.003), Kachin ethnicity (χ28=72.253, p<0.001), without formal education (χ21=3.856, p=0.050), homes near waste disposal sites (χ21=10.378, p=0.001) and refugees who have experienced flooding (χ21=5.460, p=0.019). Meanwhile, the overall seroprevalence of anti-chikungunya IgG and IgM was 9.7% (CI 7.15 to 12.73) and 10.8% (CI 8.09 to 13.93), respectively, with ages 12-18 years (χ22=6.075, p=0.048), Rohingya ethnicity (χ28=31.631, p<0.001) and homes close to waste disposal sites (χ21=3.912, p=0.048) being significant risk factors. Results showed a link to poor environmental living conditions, with an increase in the vector population with higher availability of breeding sites and thus exposure to dengue and chikungunya virus.

Conclusions: Health education among the community is the key to disease prevention, as there are no specific antiviral drugs for treatment and limited vaccine availability.

Background: The mainstay of soil-transmitted helminth (STH) control is repeated mass drug administration (MDA) of anthelmintics to endemic populations. Individual longitudinal compliance treatment patterns are important for identifying pockets of infected individuals who remain untreated and serve as infection reservoirs.

Methods: The Geshiyaro Project censused the study population in Wolaita, Ethiopia at baseline in 2018. Individual longitudinal compliance was recorded for six rounds of community-wide MDA (cMDA). The probability distribution of treatment frequency was analysed by age and gender stratifications. Probabilities of transmission interruption for different compliance patterns were calculated using an individual-based stochastic model of Ascaris lumbricoides transmission.

Results: The never-treated (0.42%) population was smaller than expected from a random positive binomial distribution. The observed compliance frequency was well described by the beta-binomial distribution. Preschool-age children (odds ratio [OR] 10.1 [95% confidence interval {CI} 6.63 to 15.4]) had the highest never-treated proportion of the age groups. Conversely, school-age children (SAC) and adults (OR 1.03 [95% CI 0.98 to 1.09]) had the highest always-treated proportion of the age groups.

Conclusions: The study reports the largest dataset of individual longitudinal compliance to cMDA for STH control. Clear pattens are shown in the age-dependent distribution of individual compliance behaviour. The impact of compliance on the probability of elimination is significant, highlighting the importance of recording the full frequency distribution, not just the never-treated proportion.

Background: Previous studies on the distribution of mycetoma globally have failed to identify Ecuador as an endemic country.

Methods: We present data on 35 cases of mycetoma in Ecuador between 1955 and 2021: 5 cases from our experience and 30 cases from the literature.

Results: Eight cases of eumycetoma (23%) and 27 cases of actinomycetoma (77%) were diagnosed. Most cases originated from the coastal region of Ecuador.

Conclusions: For the first time in an English-language publication, this communication confirms the presence of mycetoma in Ecuador, securing Ecuador's position on the global mycetoma map.

The year 2024 is the Centenary of the foundation of the Leprosy Relief Association (Lepra), formerly the British Empire Leprosy Relief Association (BELRA). The name of the organization changed to the LEProsy Relief Association (LEPRA) in 1976 but has been known as Lepra since 2008. Over the years it has worked closely with members and office holders of the Royal Society of Tropical Medicine and Hygiene. Its work has encompassed activities from the earliest initiatives to ensure appropriate living conditions for those with the disease to the development of leprosy chemotherapy. However, this has now evolved into a strong partnership between the UK- and India-based Lepra hubs, which are carrying out research and public health initiatives ranging from elimination of prejudice against those with leprosy to adopting the recently launched WHO programme for skin NTDs to facilitate integrated control and management regimens. The fight against leprosy has always been a partnership between a wide variety of disease-specific NGOs, health-care workers and international health agencies. The story of Lepra illustrates the central role of these partnerships and national as well as international collaboration.

Background: Scrub typhus is an understudied vector-borne bacterial infection.

Methods: We tested archived fever samples for scrub typhus seropositivity to begin charting its geographic distribution in Indonesia. We analysed 1033 serum samples from three sites. IgM and IgG enzyme-linked immunosorbent assay (ELISA) against Orientia tsutsugamushi was performed using Karp, Kato, Gilliam, TA 716 antigens. To determine the cutoff in the absence of a presumed unexposed population and gold standard tests, we identified the visual inflection point, performed change point analysis, and used finite mixture models.

Results: The optical density cutoff values used for IgM and IgG were 0.49 and 0.13, respectively. Across all sites, IgM seropositivity was 4.6% (95% CI: 3.4 to 6.0%) while IgG seropositivity was 4.4% (95% CI: 3.3 to 5.8%). The overall seropositivity across sites was 8.8% (95% CI: 8.1 to 11.7%). The overall seropositivity for Jambi, Denpasar, Tabanan were 9.7% (95% CI: 7.0 to 13.3%), 8.0% (95% CI: 5.7 to 11.0%), 9.0% (95% CI: 6.1 to 13.0%), respectively.

Conclusions: We conclude that O. tsutsugamushi exposure in humans occurred at all sites analysed and could be the cause of illness in some cases. Though it was not the main cause of acute fever in these locations, it is still important to consider scrub typhus in cases not responding to beta-lactam antibiotics. Future seroprevalence surveys and testing for scrub typhus in acute febrile illness studies will be essential to understand its distribution and burden in Indonesia.

Background: We estimated coverage of doxycycline chemoprophylaxis (200 mg once weekly) following floods in Kerala, India.

Methods: A cross-sectional survey was conducted to gather data on exposure to flood or stagnant water and receipt and consumption of chemoprophylaxis.

Results: Of 1573 individuals interviewed, 152 (10%) were exposed to flood water. Among these, 119 (78%) were eligible for chemoprophylaxis. Of those eligible, 58 (38.2% [95% confidence interval 30.8 to 46.1]) reported consuming the prescribed chemoprophylaxis.

Conclusions: Despite the availability of chemoprophylaxis, consumption was less than ideal. We recommend targeted interventions to improve chemoprophylaxis coverage and public awareness campaigns to enhance its consumption among the affected population.

Background: Low- and middle-income countries have a high prevalence of Helicobacter pylori infection (HPI). In Cameroon, the majority of HPIs are diagnosed and treated by primary care physicians (PCPs). We sought to assess the knowledge and practices of PCPs in the diagnosis and management of HPI in Cameroon.

Methods: A hospital-based cross-sectional study was carried out in four randomly selected regions of Cameroon from November 2021 to June 2022. In each of the selected regions, PCPs were recruited by non-probability convenience sampling and interviewed using a pre-structured questionnaire. Chi-squared, Fisher's exact and Student's t-tests were performed for descriptive analyses. Multivariable logistic regression was used to examine associations between knowledge and practice, with the model adjusted by age of the PCP, geographic region, number of patients and years in practice. Analysis was performed in SAS version 9.4 (SAS Institute, Cary, NC, USA).

Results: A total of 382 PCPs were included in the analysis. The majority (60.0%) were males between the ages of 20-29 y (64.1%). Most PCPs (80.9%) reported that HPI is the cause of gastroesophageal reflux disease and 41.8% reported that HPI is the main cause of dyspeptic symptoms. The dominant diagnostic tests used for HPI were serology (52.8%) and stool antigen (30.9%). The most frequently used first-line therapies were amoxicillin (AMX), clarithromycin (CLA), metronidazole (MNZ) and proton pump inhibitor (PPI) concomitant therapy (32.2%), AMX-CLA-PPI triple therapy (18.6%) and AMX-MNZ-PPI triple therapy (13.1%). Half of the practitioners (48.6%) treat HPI empirically, without positive H. pylori testing. About half of the PCPs (48%) do not request laboratory confirmation of H. pylori eradication following treatment.

Conclusions: There is inadequate knowledge and significant differences in the clinical approach towards HPI among PCPs in Cameroon. We recommend more teaching programs and continuous medical education on HPI.