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Introduction In 2011, member states of the World Health Organization (WHO) Africa Regional Office (AFRO) resolved to eliminate Measles by 2020. Our study aims to assess The Gambia’s progress towards the set AFRO measles elimination target and highlight surveillance and immunisation gaps to better inform future measles prevention strategies. Material and methods A retrospective review of measles surveillance data for the period 2011–2019, was extracted from The Gambia case-based measles surveillance database. WHO—UNICEF national coverage estimates were used for estimating national level MCV coverage. Measles post campaign coverage survey coverage estimates were used to estimate national measles campaign coverage. Results One hundred and twenty-five of the 863 reported suspected cases were laboratory confirmed as measles cases. More than half (53.6%) of the confirmed cases have unknown vaccination status, 24% of cases were vaccinated, 52.8% of cases occurred among males, and 72.8% cases were among urban residents. The incidence of measles cases per million population was lowest (0) in 2011–2012 and highest in 2015 and 2016 (31 and 23 respectively). The indicator for surveillance sensitivity was met in all years except in 2016 and 2019. Children aged 5–9 years (Incidence Rate Ratio—IRR = 0.6) and residents of Central River region (IRR = 0.21) had lower measles risk whilst unvaccinated (Adjusted IRR = 5.95) and those with unknown vaccination status (IRR 2.21) had higher measles risk. Vaccine effectiveness was 89.5%. Conclusion The Gambia’s quest to attain measles elimination status by 2020 has registered significant success but it is unlikely that all target indicators will be met. Vaccination has been very effective in preventing cases. There is variation in measles risk by health region, and it will be important to take it into account when designing prevention and control strategies. The quality of case investigations should be improved to enhance the quality of surveillance for decision making.

Background The poliovirus has been targeted for eradication since 1988. Kenya reported its last case of indigenous Wild Poliovirus (WPV) in 1984 but suffered from an outbreak of circulating Vaccine-derived Poliovirus type 2 (cVDPV2) in 2018. We aimed to describe Kenya’s polio surveillance performance 2016–2018 using WHO recommended polio surveillance standards. Methods Retrospective secondary data analysis was conducted using Kenyan AFP surveillance case-based database from 2016 to 2018. Analyses were carried out using Epi-Info statistical software (version 7) and mapping was done using Quantum Geographic Information System (GIS) (version 3.4.1). Results Kenya reported 1706 cases of AFP from 2016 to 2018. None of the cases were confirmed as poliomyelitis. However, 23 (1.35%) were classified as polio compatible. Children under 5 years accounted for 1085 (63.6%) cases, 937 (55.0%) cases were boys, and 1503 (88.1%) cases had received three or more doses of Oral Polio Vaccine (OPV). AFP detection rate substantially increased over the years; however, the prolonged health workers strike in 2017 negatively affected key surveillance activities. The mean Non-Polio (NP-AFP) rate during the study period was 2.87/ 100,000 children under 15 years, and two adequate specimens were collected for 1512 (88.6%) AFP cases. Cumulatively, 31 (66.0%) counties surpassed target for both WHO recommended AFP quality indicators. Conclusions The performance of Kenya’s AFP surveillance system surpassed the minimum WHO recommended targets for both non-polio AFP rate and stool adequacy during the period studied. In order to strengthen the country’s polio free status, health worker’s awareness on AFP surveillance and active case search should be strengthened in least performing counties to improve case detection. Similar analyses should be done at the sub-county level to uncover underperformance that might have been hidden by county level analysis.

Background A national mapping survey of schistosomiasis (SCH) and soil-transmitted helminthiases (STH) was conducted in The Gambia in May, 2015. The survey aimed at establishing endemicity of schistosomiasis and soil-transmitted helminthiases to inform decisions on program planning and implementation of mass drug administration (MDA). Methodology/Principal findings A cross-section of 10,434 eligible school aged children (SAC), aged 7 to 14 years old were enrolled in the survey. The participants were randomly sampled from 209 schools countrywide using N/50, where N = total eligible children per school. Stool, and urine samples were provided by each child and examined for schistosomiasis and soil-transmitted helminthic infections using double Kato-Katz, urine filtration, dipstick techniques and CCA rapid test kits. Data were managed using online LINKS system enabling real-time data availability and access. Epi Info version 3.5.3 and health mapper version 4.3.2 were used to generate outputs of endemicity and distribution. Descriptions of mapped districts for MDA eligibility and frequency were done with reference to WHO PC strategy recommendations. Mapping results indicated that nationally, the prevalence of schistosomiasis (SCH) and soil-transmitted helminthiases (STH) was 4.3% and 2.5% respectively. In terms of distribution STH are more common in Western Region One (WR1) at 4.1% prevalence, then Lower River Region (LRR) 3.6%, and Western Region Two (WR2) 3.0%. In contrast, SCH indicated much higher prevalence in Central River Region (CRR) at a rate of 14.2%. This is within medium prevalence range, and is followed by Upper River Region (URR) at 9.4%, which is within low prevalence range. At the district level, schistosomiasis prevalence seems to be highest in Niani district (22%) in CRR. Banjul island, the capital city, seems to have the highest prevalence of STH (up to 55%), followed by Kombo South with 22% prevalence. Schistosoma haematobium characterised by haematuria, was the most dominant infection of schistosomiasis discovered followed by Schistosoma mansoni which reported in 0.1% of infections. Out of 42 districts mapped 14, or 38%, of them are co-endemic for soil-transmitted helminthiases (ascariasis, trichuriasis, and hook-worm infections) and schistosomiasis (S. haematobium and S. mansoni). Conclusions We identified that 24/42(57%) districts mapped in The Gambia are endemic for schistosomiasis expressing the need for preventive chemotherapy. Twenty (47%) of the districts mapped are endemic for STH. However, only two STH endemic districts namely Banjul (55%) and Kombo South (22%) were within rates eligible for mass drug administration., Author summary The Gambia joined the international community in the fight against neglected tropical diseases (NTDs), in order to enable control and eventual elimination by year 2020. This goal is in line with Africa regional targets for NTDs control and elimination. This decision was the driving force for a tabletop analysis of the existing NTD situation in the country, culminating in the development of a comprehensive five-year NTD Master plan 2015–2020, and an Annual Work Plan 2016. The World Health Organisation regional office for Africa’s Regional Program Review Group (WHO/AFRO RPRG) supported this work by granting approval for the mapping of schistosomiasis (SCH) and soil-transmitted helminthiases (STHs) across the country in May 2015. In this publication, we describe the purpose of the survey, how the survey was conducted, and how data and specimens were collected, handled, analyzed and interpreted. We have discovered that schistosomiasis exists in twenty-four districts in the country. Most of these districts are located in the eastern half of the country in Upper and Central River Regions. This means that communities in the affected districts require treatment to reduce the burden of disease. Treatment for schistosomiasis is unlike soil-transmitted helminthiases because all districts with schistosomiasis are eligible for treatment irrespective of the level of prevalence and endemicity according to the guidelines of the World Health Organisation (WHO). In comparison to STH, mass drug administration is not required for low STH endemic communities where the prevalence was less than 20%. Instead such communities will benefit from case by case treatment STH. Mass treatment will be required in district where STH prevalence was at least moderate or 20% and above. Soil-transmitted helminthiases were found in twenty districts. However, it is important to highlight that only two of these districts, with prevalence of 22% and 55%, respectively were eligible for mass drug administration in accordance with WHO guidelines. The guidelines recommend that districts with a prevalence of soil-transmitted helminthiases of less than 20% do not require mass community treatment in order to achieve disease elimination.

Background The Gambia initiated a control programme for schistosomiasis in 2015. In light of this, recent and comprehensive data on schistosomiasis is required to effectively guide the control programme. This study aimed to evaluate the prevalence and associated risk factors of schistosomiasis among primary school children in The Gambia. Methods We utilised data from a previous study conducted in 2015 in 4 regions of The Gambia: North Bank Region (NBR), Lower River Region (LRR), Central River Region (CRR) and Upper River Region (URR). In the parent study, ten schools were selected randomly from each region. Urine and stool samples collected from 25 boys and 25 girls (7–14 years) in each school were examined for urinary schistosomiasis (Schistosoma haematobium infection) and intestinal schistosomiasis (Schistosoma mansoni infection) using urine filtration, dipstick and Kato-Katz methods. Principal findings Urinary schistosomiasis had an overall prevalence of 10.2% while intestinal schistosomiasis had a prevalence of 0.3% among the sampled school children. Prevalence of urinary schistosomiasis was significantly different among regions (χ 2 = 279.958, df = 3, p < 0.001), with CRR (27.6%) being the most endemic region, followed by URR (12.0%), then LRR (0.6%), and NBR (0.0%). Prevalence of intestinal schistosomiasis was also significantly variable among regions, with 4 of the 5 positive cases detected in CRR and 1 case in URR. Every school sampled in CRR had at least one student infected with S. haematobium, 50% of schools in URR had S. haematobium infection, and just one school in LRR had S. haematobium infection. While S. haematobium infection was significantly higher in boys (χ 2 = 4.440, df = 1, p = 0.035), no significant difference in infection rate was observed among age groups (χ 2 = 0.882, df = 2, p = 0.643). Two of the 5 students infected with S. mansoni were boys and 3 were girls. Four of these 5 students were in the 10–12 years age group and 1 was in the 7–9 years age group. Macrohaematuria and microhaematuria were found to be statistically associated with presence of S. haematobium eggs in urine. Being a male was a risk factor of S. haematobium infection. Bathing, playing and swimming in water bodies were found to pose less risk for S. haematobium infection, indicating that the true water contact behaviour of children was possibly underrepresented. Conclusion The findings of this study provide invaluable information on the prevalence of schistosomiasis in The Gambia. This was useful for the schistosomiasis control efforts of the country, as it guided mass drug administration campaigns in eligible districts in the study area. More studies on S. mansoni and its intermediate snail hosts are required to establish its true status in The Gambia. As children sometimes tend to provide responses that potentially please the research or their teacher, data collection frameworks and approaches that ensure true responses in studies involving children should be devised and used., Author summary In this study, we utilised data collected from a previous study that investigated schistosomiasis among primary school children in four regions (NBR, LRR, CRR and URR) of The Gambia, to assess the prevalence and risk factors of the disease. Our analysis revealed that urinary schistosomiasis was the most prevalent (10.2%) form of the disease and intestinal schistosomiasis was very rare (0.3%) among the school children. Urinary schistosomiasis was found in all study regions except NBR. CRR had the highest prevalence of urinary schistosomiasis and all the schools sampled in the region had at least on student with the infection. Fifty percent of schools in URR had urinary schistosomiasis infection and just one school in LRR had the infection. Presence of blood in urine was a good indicator of urinary schistosomiasis. While being male increases the chance of getting urinary schistosomiasis, playing, bathing and swimming in water bodies unexpedly turned out to pose less risk for infection, indicating the true water contact activities of the children were probably underrepresented in the data. The study provides vital information for the schistosomiasis control efforts of The Gambia. Further studies are required to know the real status of intestinal schistosomiasis in the country.

Background Studies in Sub Saharan Africa have shown that the Circulating Cathodic Antigen point-of-care-test (POC-CCA) is more accurate in the detections of S. mansoni than the microscopic Kato-Katz technique but less is known about the accuracy of this rapid test in detecting S. haematobium infections. This study was intended to evaluate the field accuracy of POC-CCA as a rapid test kit for schistosomiasis mapping in The Gambia. Methods This prospective study was conducted in 4 regions in the country. Ten schools were randomly selected from each region, and a total of 2018 participants whose ages range from 7 to 14 years were enrolled in the study. Stool and urine samples were collected from each participant from May to June 2015, and tested for S. haematobium and S. mansoni infections in field and laboratory settings. The tests conducted included POC-CCA, double Kato-Katz slides, urine filtration and dipstick for hematuria. Results Of the 1954 participants that had complete data, the mean age of participants was 9.9 years. The prevalence of children infected with S. haematobium, using urine filtration technique was 10.1% (95% CI: 8.87–11.55). Central River Region had the highest level of urinary schistosomiasis with a prevalence of 28.0% (24.13–32.12).The lowest urinary schistosomiasis prevalence of 0.6% (0.12–1.86) was found in Lower River Region and North Bank Region had no cases of schistosomiasis detected. Only 5 participants were infected with S. mansoni. Using urine filtration as reference standard for the detection of S. haematobium, the sensitivity and specificity of POC-CCA was 47.7% and 75.8%. Whilst sensitivity and specificity of POC-CCA for detecting S. mansoni were 60.0% and 71.2% using double Kato-Katz as reference standard. Conclusion This study showed lower sensitivity of POC-CCA in detecting S. haematobium. Therefore POC-CCA is less useful for rapid diagnosis of urinary schistosomiasis.

Background The Ministry of Health and Social Welfare, The Gambia with support from WHO and Task Force for Global Health (TFGH), conducted a national endemicity mapping survey for schistosomiasis (SCH) and soil-transmitted helminths (STH) to establish their endemicity status. The survey was meant to provide baseline information on endemicity in order to plan and implement strategic interventions. This is a critical step towards NTD elimination by 2020. Methods A cross-section of fifty school-aged children (SAC, 25 boys and 25 girls) per school was sampled in 209 schools countrywide. Eligible SAC of 7 to 14 years old were randomly selected using formula (n/50) where n=total eligible pupils per school. Stool, urine and finger prick samples provided, were examined for SCH and STH using Kato-Katz, urine filtration, dip-stick and CCA techniques. Results National prevalence of schistosomiasis and soil-transmitted helminthiasis were 4.3% and 2.5%, respectively. At district level, Niani had the highest prevalence of SCH, recording 22%. Whereas for STH, Banjul, the capital city, had the highest prevalence, recording 55%, followed by 22% prevalence in Kombo South. Schistosoma haematobium is the most dominant parasitic infection in The Gambia. Fourteen (38%) districts in the country are co-endemic for both STH and SCH. Generally, male pupils are more infected with urinary schistosomiasis than females. Conclusions It was established that 19 (45%) of districts mapped are endemic for schistosomiasis; thus the need for treatment with praziquantel. Twenty (47%) of districts mapped are endemic for soil-transmitted helminthiasis at varying rates. However, only two STH endemic districts, Banjul (55%), and Kombo South (22%), within the high and very high prevalence rates of endemicity, are eligible for treatment with albendazole.