Prevalence and intensity of soil-transmitted helminth infections in Uganda: Results from population-based prevalence surveys in five districts.

BACKGROUND: Soil-transmitted helminth (STH) infections are caused by roundworms (Ascaris lumbricoides), whipworms (Trichuris trichiura), and hookworms (Necator americanus and Ancylostoma duodenale). In Uganda, baseline surveys conducted during the late 1990s and early 2000s suggested STH infections were common, with prevalence >50% among surveyed schoolchildren. In 2003, a national program was launched with mass preventative chemotherapy (PC) and health education for children 1-14 years old. Little evidence is available to show the impact of national deworming. METHODS: We conducted population-based, cross-sectional household surveys in five districts (Buikwe, Kassanda, Kiryandongo, Kisoro, and Rubanda) in March and May 2022. Our primary objective was to estimate STH prevalence by species due to infections of any intensity and infections of moderate-to-heavy intensity among preschool-aged children (PSAC, 1-4 years old), school-aged children (SAC, 5-14 years old), and women of reproductive age (WRA, 15-49 years old). Laboratory technicians used duplicate Kato-Katz microscopy to determine fecal egg count. RESULTS: Overall, 3,352 PSAC; 3,884 SAC; and 1,226 WRA provided stool samples. The prevalence of any infection remained high in Kisoro at or above ~50% within all risk groups. In other districts, the prevalence of any infection ranged from approximately 5 to 16% among PSAC, 6 to 23% among SAC, and 12 to 19% among WRA. Moderate-to-heavy intensity infection prevalence was highest in Kisoro (~15-26%), followed by Rubanda (<5%), and was ≤1% in other districts. A. lumbricoides and T. trichiura infections were largely confined to Kisoro and Rubanda, whereas hookworm was most common in other districts. CONCLUSIONS: The STH prevalence has decreased markedly in three districts in Uganda. Based on our findings, the national deworming program should consider decreasing PC distribution frequency in these districts per the World Health Organization guidelines. Efforts are needed to understand why the Kisoro and Rubanda districts did not demonstrate similar gains.

Impact of a national deworming campaign on the prevalence of soil-transmitted helminthiasis in Uganda (2004-2016): Implications for national control programs.

BACKGROUND: Soil-transmitted Helminths and Anemia potentially reduce and retard cognitive and physical growth in school-age children with great implications for national control programs in Africa. After 13 years of deworming and limited health education campaigns, a study was undertaken to evaluate the impact of deworming interventions on the prevalence and intensity of soil-transmitted helminthic infections in school-age children in Uganda. METHODOLOGY: A cross-sectional study was carried out in six regions of Uganda, where two districts were randomly selected per region based on the ecological zones in the country. Included in the study were the districts; Mpigi and Nakasongola from the Central; Nakapiripirit and Kotido from Karamoja; Arua and Yumbe from West Nile; Gulu and Alebtong from the North; Kaliro and Mbale from the East; Hoima and Bundibugyo in the West. Five schools were randomly selected from each district and in each school 50 children aged 6-14 years were randomly selected. Stool samples were taken each child and examined for the presence of helminthic infections. A short pretested questionnaire was administered to each participant to obtain their knowledge, attitude, and practice relating to STH infections, their control. General observations were made on environmental sanitation in the schools. The location of each school was geo-referenced using a GPS machine (Garmin®GPSMAP62, Garmin Ltd, Southampton, UK). RESULTS: In total, 4,285 children were assessed including 719(16.82%) from central region, 718(16.80%) from eastern region, 719 (16.82%) from northern region, 689 (18.82%) from Karamoja region, 717(16.77%) from West Nile region and 723(16.91%) from western region. The average age of the children was 12.6 years with a standard deviation, SD 1.8 years and the minimum age was 6 years and upper age limit of 12 years. The percentage of boys (50.1%) and girls (49.9%) was comparable. 8.8% (95% CI; 8.0-9.7) were infected with at least any one STH species. Hookworm was the most prevalent (7.7%; 95% CI; 6.9-8.5) followed by whipworms (Trichuris trichiura) (1.3%; 95% CI; 1.0-1.7) and roundworms (Ascaris lumbricoides) (0.5%; 95% CI; 0.3-0.7). Some children had Schistosoma mansoni, 13.0% (95% CI; 12.0-14.0). All the children knew what soil transmitted helminths were (62.8%, 95% CI: 61.3-64.2) and most common knowledge of information were from; home (39%, 95% CI: 37.1-40.8), media (radio& newspaper)(11%, 95% CI: 9.8-12.2), school(65.7%, 95% CI: 63.9-67.5) and friends(11.5%, 95% CI: 10.3-12.7). Majority were aware of how one gets infected with soil transmitted helminths through; eating contaminated food (77.5%, 95% CI: 76.0-79.1), walking barefoot (59.6%, 95% CI: 57.8-61.5), drinking contaminated water (52.9%, 95% CI: 51.0-54.8), playing in dirty places (21.8%, 95% CI: 20.2-23.3) and dirty hands (2.3%, 95% CI: 1.7-2.9). CONCLUSION: Semi-annual deworming campaigns have proved effective in significantly reducing helminthic infections in most of the districts in Uganda. Regular evaluations are vital to assess impact of the interventions and guide programme implementation. Our data shows that the prevalence of infection has been reduced to a level where STH morbidity is no longer of public health importance in most districts surveyed.

The interruption of Onchocerca volvulus and Wuchereria bancrofti transmission by integrated chemotherapy in the Obongi focus, North Western Uganda.

INTERVENTION: Few studies have documented the interruption of onchocerciasis and Lymphatic Filariasis (LF) by integrated chemotherapy in Uganda. The study describes the interruption of transmission of the two diseases co-endemic in Obongi focus, north western Uganda. Base line data for Onchocerciasis and LF were collected in 1994 and 2006, respectively. Annual mass drug administration for onchocerciasis (Ivermectin) and Lymphatic Filariasis (Ivermectin + albendazole) was conducted for 20 and 6 years, respectively. Thereafter, assessments by skin snip, larval searches in rivers and human landing catches were performed. Children <10 years were screened for IgG4 antibodies using Ov16 ELISA technique in 2013. LF Pre-TAS and TAS1 were conducted in sentinel sites. ITN coverage and utilization for the implementation unit was also reported. INTERVENTION COVERAGE: Onchocerciasis treatment coverage was <80% but improved with the introduction of CDTI in 1999. While for LF, effective coverage of >65% was achieved in the six treatment rounds. Household ownership of ITN's and utilization was 96% and 72.4%., respectively. IMPACT: Parasitological examinations conducted for onchocerciasis among 807 adults and children, revealed a reduction in mf prevalence from 58% in 1994 to 0% in 2012. Entomological monitoring conducted at the two sites had no single Simulium damnosum fly caught. Serological analysis using Ov16 ELISA for onchocerciasis revealed that out of the 3,308 children <10 years old screened in 2013, only 3/3308 (0.091%) positive cases were detected. All Ov16 positive children were negative when tested for patent infection by skin snip PCR. A reduction in LF microfilaria prevalence from 2.5% (n = 13/522) in 2006 to 0.0% (n = 602) in 2014 was observed. LF TAS1 conducted in 2015 among 1,532 children 6-7 years, all were negative for antigens of W. bancrofti. CONCLUSION: The results concluded that interruption of onchocerciasis and LF has been achieved.

Prevalence of sexual coercion and its association with unwanted pregnancies among young pregnant females in Kampala, Uganda: a facility based cross-sectional study.

BACKGROUND: Sexual coercion is associated with sexually transmitted infections and unwanted pregnancies with consequential unsafe abortions and increased maternal morbidity and mortality. Current literature focuses mainly on its risk factors but less on its resultant deleterious health effects. We conducted a study to determine the prevalence of sexual coercion and its association with unwanted pregnancies among young pregnant women. METHODS: In a cross-sectional study, four hundred and sixteen (416) consenting pregnant females aged 15-24 years attending antenatal clinics in Lubaga division Kampala district in Uganda were enrolled using systematic sampling. Quantitative and qualitative data on sexual coercion were collected by female interviewers. Adjusted Prevalence Proportion Ratios (Adj. PPRs) of unwanted pregnancy and associated 95 % confidence intervals were estimated by generalized linear models with log link function and Poisson family distribution using robust variance estimator. Quantitative data were analyzed using Stata version 10.0, while qualitative data were analyzed using manifest content analysis. RESULTS: Prevalence of sexual coercion was 24 % and was higher among those who had non consensual sexual debut (29.0 %) compared with those who had consensual sexual debut (22.6 %). The prevalence of unwanted pregnancy was 18.3 % and was higher among participants who had been sexually coerced relative to their counterparts (p < 0.001). History of sexual coercion in the past 12 months and non consensual sexual debut were associated with unwanted pregnancy [adj.PPR = 2.23, 95 % CI: (1.49-3.32)] and 1.72, 95 % CI: (1.16- 2.54)] respectively. Qualitative results indicated that different forms/contexts of sexual coercion, such as deception, transactional sex and physical force influenced unwanted pregnancies. DISCUSSION: This study highlights that a quarter of our participants in our quantitative study had experienced sexual coercion in the past twelve months and nearly a third of these, had history of non consensual sexual debut. Unwanted pregnancy was higher among the sexually coerced and those who had non consensual sexual debut. CONCLUSION: Sexual coercion among pregnant women aged 15-24 years in Kampala, Uganda is high and is significantly associated with unwanted pregnancy. Comprehensive sex education targeting young people (<25 years), along with availability and access to youth friendly centers may be useful in addressing sexual coercion and its negative outcomes.

Community perceptions, attitude, practices and treatment seeking behaviour for schistosomiasis in L. Victoria islands in Uganda.

BACKGROUND: Over 200,000 people, most of them infected with Schistosoma mansoni inhabit 150 islands in Lake Victoria in Uganda. Although a programme to control the disease has been ongoing since 2003, its implementation in islands is inadequate due to high transport costs on water. In 2011 and 2012, the Global Network for Neglected Tropical Diseases (GNNTD) through Schistosomiasis Control Initiative (SCI) provided financial support to ease treatment delivery on the islands and over the period, therapeutic coverage has been increasing. We conducted a study with an objective to assess community awareness of existence of the disease, its signs, symptoms, causes and transmission as well as attitude, practice and health seeking behavior. METHODS: This was a cross sectional descriptive study which used pre-tested interviewer administered questionnaire among purposively selected individuals in schools, health facilities and communities. Frequency distribution tables, graphs and cross tabulations were the main forms of data presentation. RESULTS: Our results showed that there are numerous challenges that must be overcome to achieve effective control of schistosomiasis in the islands. Many people especially young men are constantly on the move from island to island in search for richer fishing grounds and such groups are commonly known to miss treatment by mass chemotherapy. Unfortunately case management in health facilities is very poor; health facilities are few and understaffed mainly with unskilled personnel who are overburdened by other illnesses such as malaria and HIV and the supply of praziquantel in health facilities is inadequate. Furthermore, sanitation is appalling, no clean water and community knowledge about schistosomiasis is low even among biomedical staff. CONCLUSION: Rather than elimination, our results indicate that the programme should continue to target morbidity control beyond the 2020s until preventive measures have been instituted. The government should provide adequate trained health workers and stock praziquantel in all island health facilities.

Compatibility of Ugandan Schistosoma mansoni isolates with Biomphalaria snail species from Lake Albert and Lake Victoria.

In order to investigate the capacity of being intermediate host for Schistosoma mansoni, the Ugandan F1 generation of Biomphalaria snail species that were laboratory-bred from parent populations originally collected from either Lake Victoria or Lake Albert was challenged with sympatric and non-sympatric S. mansoni isolates. After a prepatent period of 20 days, a daily 10-hourly snail shedding for cercariae was done to determine the infection rate, cercarial production per hour and survival period of infected snails. The study suggests that when parasite strains from a different geographical origin is used for infection, survival of infected snails increase, leading to an increased transmission potential. Although earlier literature had indicated that the Lake Victoria Biomphalaria sudanica is refractory to S. mansoni, we showed that all Ugandan Biomphalaria spp., including B. sudanica from all locations, were highly susceptible to the S. mansoni isolates. Thus if B. choanomphala, which is an efficient intermediate host in Lake Victoria, is given an opportunity to occupy Lake Albert, it will most likely be compatible with the Albertine S. mansoni parasites. Equally, if B. stanleyi, currently restricted to Lake Albert invades Lake Victoria, it is likely to act as an efficient intermediate host. Future work should concentrate on intraspecific population-level differences in compatibility.