Two Nigerian States (Plateau and Nasarawa) Have Eliminated Transmission of Human Onchocerciasis-A Report of Post-Ivermectin Mass Drug Administration Surveillance.

Transmission of Onchocerca volvulus (causing "river blindness") was interrupted in two states of Nigeria (Plateau and Nasarawa) in 2017 in accordance with 2016 WHO guidelines. Ivermectin mass drug administration was halted in January 2018, and posttreatment surveillance activities were conducted over a 3-year period. Vector Simulium damnosum s.l. flies were collected during the 2019 (39 sites) and 2020 (42 sites) transmission seasons. Head pools were tested by polymerase chain reaction for the presence of third-stage O. volvulus larvae; 15,585 flies were all negative, demonstrating an infective rate of < 1/2,000 with 95% confidence. In 2021, the Nigerian Federal Ministry of Health declared the two-state area as having eliminated transmission. Plateau and Nasarawa states are the first of 30 endemic states in Nigeria to have met the WHO criteria for onchocerciasis elimination. Post-elimination surveillance will need to continue given the risk of reintroduction of transmission from neighboring states.

The Interruption of Transmission of Human Onchocerciasis by an Annual Mass Drug Administration Program in Plateau and Nasarawa States, Nigeria.

Plateau and Nasarawa states in central Nigeria were endemic for onchocerciasis. The rural populations of these two states received annual ivermectin mass drug administration (MDA) for a period of 8-26 years (1992-2017). Ivermectin combined with albendazole was given for 8-13 of these years for lymphatic filariasis (LF); the LF MDA program successfully concluded in 2012, but ivermectin MDA continued in areas known to have a baseline meso-/hyperendemic onchocerciasis. In 2017, serological and entomological assessments were undertaken to determine if MDA for onchocerciasis could be stopped in accordance with the current WHO guidelines. Surveys were conducted in 39 sites that included testing 5- to < 10-year-old resident children by using ELISA for OV16 IgG4 antibodies, and Onchocerca volvulus O150 pooled polymerase chain reaction (PCR) testing of Simulium damnosum s.l. vector heads. Only two of 6,262 children were OV16 positive, and none of 19,056 vector heads were positive for parasite DNA. Therefore, both states were able to meet WHO stop-MDA thresholds of an infection rate in children of < 0.1% and a rate of infective blackflies of <1/2,000, with 95% statistical confidence. Transmission of onchocerciasis was declared interrupted in Plateau and Nasarawa states by the Federal Ministry of Health, and 2.2 million ivermectin treatments/year were stopped in 2018. Post-treatment Surveillance was launched focusing on entomological monitoring on borders with neighboring onchocerciasis-endemic states. An apparent positive impact of the LF MDA program on eliminating hypo-endemic onchocerciasis was observed. This is the first stop-MDA decision for onchocerciasis in Nigeria and the largest single stop-MDA decision for onchocerciasis yet reported. This achievement, along with the process used in adapting and implementing the 2016 WHO stop-MDA guidelines, will be important as a potential model for decision makers and national onchocerciasis elimination committees in other African countries that are charged with advancing their programs.

The positive influence the Onchocerciasis Elimination Program for the Americas has had on Africa programs.

A recent article "Is onchocerciasis elimination in Africa feasible by 2025: a perspective based on lessons learnt from the African control programmes" in Infectious Diseases of Poverty claimed that undue influence on African programs by concepts developed by the Onchocerciasis Elimination Program of the Americas (OEPA) is detrimental to stopping mass drug administration (MDA) in Africa. This claim is made despite a record year for MDA stoppage in four African countries of > 3.5 million treatments in 2018, far exceeding any past OEPA or African Program for Onchocerciasis Control (APOC) stop MDA success.

Perceptions on the use of insecticide treated nets in parts of the Imo River Basin, Nigeria: implications for preventing malaria in pregnancy.

This study aimed at assessing perceptions on use of ITNs in parts of the Imo River Basin, Nigeria and its implications in preventing malaria in pregnancy. Data was collected using focus group discussions, key informant interviews and structured questionnaires. Results showed high awareness on the benefits of ITNs. Factors affecting use of ITNs included its high cost, perceptions of chemicals used to treat them as having dangerous effects on pregnancy, low utilization of antenatal care, husband's lack of interest in malaria prevention and perceptions that adolescent girls are at low risk of getting malaria. The implications of these findings include demystifying the negative perceptions on the chemicals used for net treatment and subsidizing the cost of ITNs to increase access. These findings provide important lessons for malaria programmes that aim at increasing access to ITNs by pregnant women in developing countries.

Placental malaria in Owerri, Imo State, south-eastern Nigeria.

Malaria in pregnancy jeopardizes the outcome of pregnancy, affecting both the mother and the foetus. The prevalence of placental malaria in women, who routinely attended ante-natal clinics in Owerri, south-eastern Nigeria, was assessed using three hospitals between March 2004 and August 2005. Placental blood was collected in EDTA bottles from incisions made on cleaned basal plate of the placenta, within an hour of delivery. Blood collected was used to assess ABO blood group, haemoglobin level as well as malaria parasitaemia. Malaria parasitaemia was determined from thick and thin smears stained with Giemsa, while the haemoglobin level was measured using the cyanomethaemoglobin method. A total of 586 pregnant women were involved in this study with written consents. Malaria parasites were observed in 175 (29.9%) of the women on delivery. Of these women, 64 (36.6%) were anaemic. A significant relationship at P<0.05 variation, was observed between the prevalence of malaria parasites in the placenta and gravidity, age and blood group. The rate of occurrence of malaria parasitaemia, in the placenta of women who were on a weekly prophylaxis against malaria is alarming and calls for more serious efforts in the prevention of malaria especially in this vulnerable group.

The varied beneficial effects of ivermectin (Mectizan) treatment, as observed within onchocerciasis foci in south-eastern Nigeria.

In the treatment of humans, ivermectin (Mectizan((R))), a semi-synthetic macrocyclic lactone, is now primarily used as a rapid microfilaricide. The drug has several other benefits, however, and these have recently been investigated in five states in south-eastern Nigeria, where there have been mass treatments with ivermectin, for the control of Onchocerca volvulus, for more than 10 years. Between the January and December of 2005, 3125 adult onchocerciasis patients (each aged >/=20 years and known to have at least one clinical sign of onchocerciasis) were enlisted, clinically examined and interviewed. Relevant data were collected in the interviews, using a structured, pre-tested questionnaire, and in personal and focus-group discussions. Overall, 612 (19.6%) of the subjects reported that they had had nodules that had disappeared following repeated doses of ivermectin, although only 83.8% of the 612 attributed their nodule clearance to ivermectin (the other 16.2% being unsure of the cause). A larger percentage of the subjects (24.6%) reported that they had expelled intestinal helminths following the last round of ivermectin treatment (i.e. been dewormed). Other side-benefits reported in the study were improved vision (11.7% of subjects), reversal of secondary amenorrhea (4.5%), increased appetite (22.3%), reduction in arthritic or other musculo-skeletal pain (7.9%), reductions in the severity of body itching (18.5%) and skin rash (17.3%), darkening of leopard skin (6.6%), improved libido in men (6.6%), and clearance of head lice (4.5%). If, via health education, the local communities could be made more aware of the side-benefits of ivermectin treatment, the sustainability of the on-going programme of community-directed treatment with ivermectin (CDTI) in south-eastern Nigeria would probably be improved.

The use of herbs in malaria treatment in parts of Imo State, Nigeria.

Persistence of malaria symptoms after treatment with over the counter available antimalarial drugs has resulted in a gradual loss of faith in orthodox drugs. There is thus an increased tendency towards the use of herbs in the treatment of malaria in Imo State, Nigeria. In this study we report activities of two herbalists in the treatment of malaria as well as the effectiveness of the herbal treatment. The study covered two areas namely, Umuneke Ugiri in Isiala Mbano Local Government Area (LGA) and Odummara Obi-Orodo in Mbaitoli LGA of Imo State, Nigeria. A participant-observation technique was used. Finger prick blood samples were collected from patients who visited the herbalists complaining of malaria, and blood smears were stained with Field's B stain. Blood smears were taken again one-week post-treatment. A total of 75 patients from Umuneke Ugiri and 265 patients from Odumara Obi-Orodo were involved in the study. All the 75 patients (100%) from Umuneke Ugiri and 163 (61.51%) patients from Odummara Obi-Orodo were positive for malaria parasites. Only 13 (17.3%) patients from Umuneke Ugiri and 149 (56.23%) from Odummara Obi-Orodo returned for the post-treatment blood parasite analysis. From Umuneke Ugiri 4 (31%) were still positive for malaria parasite while 9 (69%) were negative. All 149 patients from Odummara Obi-Orodo were negative. This indicates that the herbal treatment was effective. However, there is need for further studies into the efficacy of herbal concoctions, their effective life span, as well as possible toxic effects.

Concomitant bacteria in the blood of malaria patients in Owerri, southeastern Nigeria.

The presence of concomitant bacteria was assessed in the blood of 125 malaria positive patients and 60 malaria negative controls, resident in Owerri, southeastern Nigeria. Blood samples were cultured in MacConkey, Chocolate and Blood agar, respectively using oxoid signal system after the manufacturer's instructions. Blood cultures of 44 (35.2%) of the 125 malaria positive patients had bacterial growth while none was observed in the blood cultures of malaria negative patients. The bacteria species identified included: Staphylococcus aureus 4 (3.2%), Escherichia coli 3 (2.4%) Salmonella typhi 25 (20%), Klebsiella pneumoniae 10 (2.4%) and Pseudomonas aeruginosa 2 (1.6%). The presence of concomitant bacteria in malaria-positive cases usually results in persistence of malaria-like symptoms after treatment with antimalarials and subsequently taken as resistance of the parasites to the particular drugs in question. The significance of concomitant bacteria in the management of malaria should be given priority.

Rapid epidemiological mapping of onchocerciasis (REMO): its application by the African Programme for Onchocerciasis Control (APOC).

One of the fundamental challenges that the African Programme for Onchocerciasis Control (APOC) has had to face is how to identify the endemic communities where its mass ivermectin-treatment operations are to be carried out in conformity with its stated objective of targetting the most highly endemic, affected and at-risk populations. This it has done by adopting a technique, known as the rapid epidemiological mapping of onchocerciasis (REMO), that provides data on the distribution and prevalence of onchocerciasis. Integration of the REMO data into a geographical information system (GIS) enables delineation of zones of various levels of endemicity, and this is an important step in the planning process for onchocerciasis control. Zones are included in (or excluded from) the APOC-funded programme of community-directed treatment with ivermectin (CDTI), depending on whether or not their levels of onchocercal endemicity reach the threshold set by APOC. This review describes the application of the REMO/GIS technique by APOC in its operations, and identifies the remaining related challenges.