Observed Reductions in Schistosoma mansoni Transmission from Large-Scale Administration of Praziquantel in Uganda: A Mathematical Modelling Study

To date schistosomiasis control programmes based on chemotherapy have largely aimed at controlling morbidity in treated individuals rather than at suppressing transmission. In this study, a mathematical modelling approach was used to estimate reductions in the rate of Schistosoma mansoni reinfection following annual mass drug administration (MDA) with praziquantel in Uganda over four years (2003-2006). In doing this we aim to elucidate the benefits of MDA in reducing community transmission.Age-structured models were fitted to a longitudinal cohort followed up across successive rounds of annual treatment for four years (Baseline: 2003, TREATMENT: 2004-2006; n = 1,764). Instead of modelling contamination, infection and immunity processes separately, these functions were combined in order to estimate a composite force of infection (FOI), i.e., the rate of parasite acquisition by hosts.MDA achieved substantial and statistically significant reductions in the FOI following one round of treatment in areas of low baseline infection intensity, and following two rounds in areas with high and medium intensities. In all areas, the FOI remained suppressed following a third round of treatment.This study represents one of the first attempts to monitor reductions in the FOI within a large-scale MDA schistosomiasis morbidity control programme in sub-Saharan Africa. The results indicate that the Schistosomiasis Control Initiative, as a model for other MDA programmes, is likely exerting a significant ancillary impact on reducing transmission within the community, and may provide health benefits to those who do not receive treatment. The results obtained will have implications for evaluating the cost-effectiveness of schistosomiasis control programmes and the design of monitoring and evaluation approaches in general

Brucellosis as an Emerging Threat in Developing Economies:Lessons from Nigeria

Nigeria is the most populous country in Africa, has a large proportion of the world's poor livestock keepers, and is a hotspot for neglected zoonoses. A review of the 127 accessible publications on brucellosis in Nigeria reveals only scant and fragmented evidence on its spatial and temporal distribution in different epidemiological contexts. The few bacteriological studies conducted demonstrate the existence of Brucella abortus in cattle and sheep, but evidence for B. melitensis in small ruminants is dated and unclear. The bulk of the evidence consists of seroprevalence studies, but test standardization and validation are not always adequately described, and misinterpretations exist with regard to sensitivity and/or specificity and ability to identify the infecting Brucella species. Despite this, early studies suggest that although brucellosis was endemic in extensive nomadic systems, seroprevalence was low, and brucellosis was not perceived as a real burden; recent studies, however, may reflect a changing trend. Concerning human brucellosis, no studies have identified the Brucella species and most reports provide only serological evidence of contact with Brucella in the classical risk groups; some suggest brucellosis misdiagnoses as malaria or other febrile conditions. The investigation of a severe outbreak that occurred in the late 1970s describes the emergence of animal and human disease caused by the settling of previously nomadic populations during the Sahelian drought. There appears to be an increasing risk of re-emergence of brucellosis in sub-Saharan Africa, as a result of the co-existence of pastoralist movements and the increase of intensive management resulting from growing urbanization and food demand. Highly contagious zoonoses like brucellosis pose a threat with far-reaching social and political consequences

Evaluation and Validation of the Questionnaire Approach for the Diagnosis of Urinary Schistosomiasis amongst Nigerian School Pupils

Urinary schistosomiasis is endemic in some parts of Cross River State, in Nigeria. Due to the prohibitive cost of diagnosis and the focal nature of the disease, endemic areas cannot be easily delineated for control operations. In this study, we report the outcome of our assessment of the newly introduced questionnaire approach in the diagnosis of urinary schistosomiasis amongst 5,453 pupils and also validated its performance among a subset of 310 pupils in Biase Local Government Area. The questionnaire which enquired whether pupils had urinary schistosomiasis or blood in their urine in the preceding month, was administered by class teachers to the pupils. Urine samples collected for the validation of the questionnaire diagnosis was also examined using dipsticks (by teachers and the research team) and for the presence of ova of Schistosoma haematobium. There was a strong positive correlation between the pupil's knowledge of schistosomiasis as a disease and the reported presence of blood in urine (r=0.96) although the later was a better indicator of the disease. The questionnaire technique (blood in urine) gave a comparable sensitivity (85.8%), specificity (81.4%), positive and negative predictive values (96.6% and 47.9%) to the dipstick test with values of 93.6%, 88.4%, 98% and 69.1% respectively. Age had a statistically significant influence on the results of the different survey techniques (P 0.05). Teachers were able to detect haematuria with a high level of accuracy. We found this approach to be simple, cost-effect and reliable and have recommended its usage in other endemic settings with large land mass and dense populations like Nigeria. Key Words: Schistosomiasis, Diagnosis, Questionnaire, Cross River , Nigeria. Mary Slessor Journal of Medicine Vol.4(1) 2004: 63-7

Epidemiology of Paragonimiasis in Oban Community of Cross River State, Nigeria.

Abstract: The epidemiology and perception of Paragonimus infection were investigated in Oban community of Cross River State, Nigeria between January and June, 2006. Sputum samples collected on each of three consecutive days from 311 participants with productive cough were examined using standard parasitological procedures for the detection of ova of Paragonimus Spp. The samples were also processed and stained using the Ziehl-Neelsen technique to exclude Mycobacterium tuberculosis infection. Crabs collected from the village streams were dissected and examined for the presence of metacercariae of Paragonimus Spp. A questionnaire was also administered to test the perception of the disease.Paragonimus uterobilateralis was confirmed as the aetiologic agent of paragonimiasis with a prevalence of 4.2%. Peak prevalence of 7.7% was found among children aged between 1 to 10 years. More males (4.5%) were infected than females (3.9%) (P > 0.05). The mean egg count was high (222 egs/5ml of sputum). The intensity of infection was found tocorrelate moderately and strongly with haemoptysis (r = 0.6) and chest pain (r=0.8) respectively. Only 1.6% of the subjects had tuberculosis and presented with symptoms which mimic paragonimiasis. Sudanonautes africanus is the suspected vector of the disease in this locality. The disease, its vector and mode of transmission were poorly perceived by therespondents. The study has confirmed the endemicity of paragonimiasis in Oban community as well as provides comprehensive information on the disease and its transmission in this locality. There is urgent need to initiate the control of this disease in this community

Pharmacological Screening and Evaluation of Antiplasmodial Activity of Gongronema latifolium (utazi) Against Plasmodium berghei berghei infection in Mice

The antiplasmodial activity of the ethanolic leaf extract of Gongronema latifolium on chloroquine-sensitive Plasmodium berghi berghi infection in mice was investigated in Calabar, Nigeria to assess its traditional use as an antimalarial remedy in Nigeria. The schizonticidal activity of the extract and that of chloroquine were determined in mice. The pharmacological property of the leaf was also assessed using standard procedures. The LD­50 of the extract was estimated using Swiss Albino mice by intraperitoneal route. The extract was found to produce an insignificant chemosuppressive effect during early and established infection. There was a dose dependent reduction in parasitaemia in the extract-treated group which was more pronounced with the highest dose of the extract (750mg/kg). The study has shown that the leaf extract possesses a weak schizonticidal activity that may not be adequate for the treatment of malaria but may be sufficient to alleviate symptoms of malaria like inflammation, pains and fever, thus acting in a similar manner to the analgesic drugs. Keywords: Pharmacological, Antiplasmodial, Gongronema latifolium Nigerian Journal of Health and Biomedical Sciences Vol. 7 (2) 2008: pp. 51-5

The Assessment of Effectiveness of Immunization in the Control of Infectious Childhood Diseases in Nigeria

Childhood immunization remains an important strategy in the reduction of morbidity and mortality from common vaccine preventable diseases. Nigeria’s immunization coverage rates are among the lowest in the world. This low coverage rate can be attributed to challenges encountered by the programme. A quick turn around came in December 2005 when the World Health Organisation – Nigeria Expanded programme on immunization team supported a Government of Nigeria consultative process to strengthen routine immunization using a 4 – point strategy. This strong partnership resulted in the increase of routine immunization coverage of Diptheria-Pertussis-Tetanus 3 from 37.5% in December 2005 to 72% by end of December 2006. There was a decline in the transmission of wild polio virus type 1. Only 22% of the 1129 polio cases confirmed in 2006 occurred during the second half of 2006; the number of children never vaccinated with OPV also declined from 50% to 20%. Enhanced surveillance for measles has demonstrated the dramatic reduction in measles morbidity and mortality rate from 144,068 cases in 2005 with a case fatality rate of >4% to 16,629 cases in 2006 with a case fatalityrate of 1.8%. Also, 26 million (83%) children under age five were also vaccinated for measles during the integrated measles campaign in 17 southern states in October 2006. The challenges encountered by the Nigerian’s immunization programme include inadequate vaccination supplies, collapse of primary healthcare services, poor acceptance ofimmunization particularly in northern Nigeria, civil unrest, wars, natural disasters and others

Assessment of haematuria and proteinuria as diagnostic markers for monitoring treatment of urinary schistosomiasis with artesunate

Oral artesunate although originally manufactured for the treatment of malaria has recently been shown to be effective in the treatment of S. haematobium infection. The usage of the presence/absence of haematuria and proteinuria in monitoring the outcome of treatment of urinary schistosomiasis patients with artesunate was assessed in the present study. The mean ova count, haematuria and proteinuria of 87 infected subjects who were treated were significantly reduced from 55.5 ± 1.3 ova/10ml, 168.6 ± 1.23 eryl/&mu;gl and 458.6 ± 1.40 mg/dl to 1.8 ± 0 ova/10ml, 9.1 ± 0.4 eryl/&mu;gl and 65.4 ± 1.64mg/dl respectively (P < 0.05 in all cases). This effect was also demonstrated by gender. It is concluded that reagent strips (Haematuria and proteinuria) are reliable in monitoring the efficacy of artesunate. Keywords; urinary schistosomiasis, treatment, artesunate, diagnostic markers Mary Slessor Journal of Medicine Vol. 5(1), 2005: 1-

Prevalence of urinary schistosomiasis among school children in Ukwelo-Obudu and Abini communities in Cross River State, Nigeria

Background: The prevalence and intensity of Schistosoma haematobium infection were studied in Ukwelo-Obudu, and Abini communities of Cross River State, Nigeria.  Aim: To screen for the presence of ova of S. haematobium in the urine of school children in the two communities. Method: Six hundred urine specimens (400 in Abini and 200 in Ukwelo-Obudu community) were collected by random sampling from school children aged 5-17 years from the two communities and screened for ova of Schistosoma haematobium by filtration of urine and counting of filtered carbol fuchsin-stained eggs of Schistosoma haematobium. Retrospective study of Schistosoma haematobium infection was also carried out in Ukwelo-Obudu community. Results: Infection with S. haematobium was not found in Ukwelo-Obudu whereas in Abini community, a prevalence of 4.5% was found. The highest prevalence of infection (7.7%) occurred in the age group of 11-13 years. There was a strong positive correlation between the presence of infection (ova of S. haematobium) and existence of haematuria (r = 0.81) and proteinuria (r = 0.71) in Abini community. There was a statistically significant difference in the prevalence of proteinuria between male and female subjects examined (P=0.0008). A retrospective study of Schistosoma haematobium infection in Ukwelo-Obudu community showed 2006 as the year with the highest record of infection [11(35.5%)] whereas the year 2004 recorded the lowest number of infection. Conclusion: This study has revealed a low prevalence of Schistosoma haematobium infection in Abini and the absence of infection in Ukwelo-Obudu communities respectively.   Key words: Prevalence, Schistosoma haematobium, Abini, Ukwelo-obudu, School children