Prevalence of Lassa virus among rodents trapped in three South-South States of Nigeria.

BACKGROUND & OBJECTIVES: Lassa fever has been endemic in Nigeria since 1969. The rodent Mastomys natalensis has been widely claimed to be the reservoir host of the Lassa virus. This study was designed to investigate the dis- tribution of species of rodents in three states (Edo, Delta and Bayelsa) of Nigeria and to determine the prevalence of Lassa virus amongst trapped rodents in the selected states. METHODS: Rodents were trapped during November 2015 to October 2016 from the three states in South-South re- gion of Nigeria. Total RNA was extracted from the blood collected from the trapped rodents. Reverse transcription polymerase chain reaction (RT-PCR) was used to confirm the presence of Lassa virus in the rodents. RESULTS: The results revealed that six species of rodents were predominantly present in these geographical locations. Mus musculus (39.4%) had the highest prevalence, closely followed by Rattus rattus (36.1%), R. fuscipus (20.3%), M. natalensis (2%), Myosoricinae soricidae (1.2%) and R. norvegicus (1%). The overall positivity (carrier rate) of Lassa virus was 1.6% amongst the 1500 rodents caught in the three states. In Edo and Delta States, the RT-PCR results showed presence of Lassa virus in R. rattus, M. musculus and M. natalensis. On the other hand, only M. na- talensis was detected with the virus, amongst the species of rodents caught in Bayelsa State. M. natalensis recorded the highest Lassa virus among rodents trapped in Edo (87%), Delta (50%) and Bayelsa (11%) States respectively. INTERPRETATION & CONCLUSION: The rather low Lassa virus positive among rodents in Bayelsa State of Nigeria may explain the absence of reports of outbreak of Lassa fever over the past 48 yr in the state. The results also confirmed that apart from Mastomys natalensis, other rodents such as Rattus rattus and Mus musculus may also serve as res- ervoirs for Lassa virus. From the findings of this cross-sectional study, it was concluded that a more comprehensive study on rodents as reservoir host, need to be undertaken across the entire states of Nigeria, for better understanding of the epidemiology and endemicity of Lassa fever.

Candida species amongst pregnant women in Benin city, Nigeria: effect of predisposing factors

Genital samples from pregnant women were examined to determine the Candida species present and how some predisposing factors would affect the frequency of isolation of species. A total of 147 women (87 volunteer asymptomatic pregnant women and 60 asymptomatic nonpregnant women) were examined. High Vaginal Swabs (HVS) were collected in pairs while demographic data (age of individual; age of pregnancy; occupation and use of contraceptive pill) on each subject were obtained alongside. Samples were cultured on Sabouraud Dextrose Agar plates and incubated for 72 hours at 37oC. Results revealed five Candida species (C.albicans; C.glabrata; C.tropicalis; C.stellatoidea; C.parapsilosis) with 61.5; 17.9; 7.7; 5.1; 2.6frequency of isolation respectively; as against 73.7; 7.7; 1.4; 11.3; and 0.0for control. Women in the second trimester of pregnancy had the highest occurrence (68.8) while the age groups 24- 30 and 31-37 years had the highest occurrence in the control (46.2) and in the pregnant ones (51.7) respectively. Traders had 68.8; and full-time housewives; 26.7occurrence. More women who used contraceptives had Candida (58.3) as against non contraceptive users (35.3). The results support literature reports that there are high rates of colonization of the vagina of pregnant women by Candida. They also give credence to earlier reports that the factors determined here affect the frequency of isolation of Candida species from the vagina