Asian Pacific Journal of Tropical Disease

199-204

Authors: Benson Chuks Iweriebor, Aboi Igwaran, Abiodun Atinuke Adegborioye, Elia John Mmbaga, Anthony Ifeanyi Okoh, Larry Chikwelu Obi

Objective: To profile ticks collected from domestic animals and vegetation for the presence of Rickettsial pathogens. Methods: Ticks were collected from domesticated animals and from vegetation in some selected communities. A total of 900 adults and nymphs ticks were collected. They were identified by taxonomic morphological criteria and screened for the detection of Rickettsia genetic material using citrate synthase (gltA) gene specific primers to produced 610 bp amplicons which were sequenced and analyzed. Results: The ticks collected were identified as belonging to three genera which were Rhipicephalus, Amblyomma, and Hyalomma, in decreasing order of their abundance. Rickettsial genetic material was detected in 15/900(1.67%) of the samples. Analyses of the generated sequences showed that five are phylogenetically related to members of the spotted fever group (SFG) rickettsia while the remaining ten sequences were Candidatus Rickettsia spp. whose pathogenic potentials are not known. The SFG rickettsia was of the genera Rickettsia akari and Rickettsia raoultii both being reported in South Africa for the first time and also in Rhipicephalus spp. as a vector. Conclusions: This finding thus shows that ticks in South Africa harbor Rickettsia akari and Rickettsia raoultii and are capable of transmitting it to infested humans.

211-219

Authors: Tsige Ketema, Ketema Bacha, Moti Yohannes, Esayas Alemayehu, Argaw Ambelu

Objective: To assess effect of nicotine, major addictive component of tobacco smoke, on outcomes of the deadly malaria parasite using mice as animal model. Methods: Male Swiss albino mice were treated with 100 and 200 µg/mL of nicotine in drinking water daily for 6 weeks followed by Plasmodium berghei ANKA (PbA) infection. On the seventh day of post infection (p.i.), physical, clinical, histopathological, biochemical and hematological parameters were assessed. Data were analyzed using SPSS software. Results: Nicotine was significantly (P < 0.05) positively associated with lower levels of hemoglobin (Hb), hematocrit (HCT), red blood cells (RBCs), C-reactive protein (CRP) and uric acid (UA), higher risk to incidence of pulmonary edema, elevated level of liver and kidney biomarkers. Also significant increment (P < 0.01) of monocyte-lymphocyte count ratio (MLCR) was observed. Risk to high temperature, lower platelet count, high parastemia and cerebral malaria was lesser in mice treated with nicotine (100 and 200 µg/mL) followed by PbA infection than the positive control. Lack of neurological symptoms might be accounted to the anti-inflammatory property of nicotine that could inhibit production of pro-inflammatory mediators responsible for occurrence of cerebral malaria. Conclusions: This study showed that despite down regulation of most cerebral malaria symptoms nicotine was strongly associated with increased risk to most clinical symptoms of malaria. Thus, like in respiratory infections, nicotine use might enhance susceptibility to malaria.

225-232

Authors: Mekonnen Assefa, Alemayehu Worku, Aman Yesuf

Objective: To compare the HIV free survival and morbidity of breast- and formula-fed infants and young children of HIV infected women in the prevention of mother to child HIV transmission program. Methods: Retrospective cohort study designs were employed from September 12, 2008 to February 28, 2014 to compare free HIV survival of exposed infants and young children whose age is < 18 months and were on breast-fed and formula-fed. Data were retrieved from 857 randomly selected study subjects (291 formula-fed and 566 breast-fed infants and young children). Morbidity and HIV infection (the counterpart of HIV-free survival) in the two feeding modalities were compared by using Kaplan-Meier time-to-event methods and log rank test was used to compare HIV free survival between the two groups. Cox regression analysis was employed to assess the independent predictors. Results: Overall probability of HIV free survival in formula-fed infants and young children was significantly higher than breast-fed infants and young children (log rank test statistics = 6.13, df = 1, P = 0.013). Breast-fed infants and young children had four (adjusted HR = 3.8, 95% CI 1.3–11.1) times higher risks to acquire HIV infection as compared to formula-fed infants and young children. Mothers who didn’t use any prevention of mother to child transmission of HIV intervention had five fold risk to transmit HIV infection to their infants than their counterparts (adjusted HR = 4.8, 95%CI 1.1–22.5). There was no statistically significant difference in the risk of developing any types of morbidity between the two groups. Conclusions: The 18 months cumulative likelihood of HIV free survival was significantly lower in the breast-fed infants and young children as compared to formula-fed infants and young children.

237-238

Authors: Shah Muhammad Haroon, Muhammad Sohail Afzal

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