262 research outputs found
Relative fitness contribution of BoLA alleles in T.parva immune cattle: Interface with parasite genetic diversity
FIGO postpartum intrauterine device initiative: Complication rates across six countries.
OBJECTIVE: To record and analyze complication rates following postpartum intrauterine device (PPIUD) insertion in 48 hospitals in six countries: Sri Lanka, India, Nepal, Bangladesh, Tanzania, and Kenya. METHODS: Healthcare providers were trained in counselling and insertion of PPIUD via a training-the-trainer model. Data were collected on methodology, timing, cadre of staff providing care, and number of insertions. Data on complications were collected at 6-week follow-up. Statistical analysis was performed to elucidate factors associated with increased expulsion and absence of threads. RESULTS: From May 2014 to September 2017, 36 766 PPIUDs were inserted: 53% vaginal and 47% at cesarean delivery; 74% were inserted by doctors. Follow-up was attended by 52%. Expulsion and removal rates were 2.5% and 3.6%, respectively. Threads were not visible in 29%. Expulsion was less likely after cesarean insertion (aOR 0.33; 95% CI, 0.26-0.41), following vaginal insertion at between 10 minutes and 48 hours (aOR 0.59; 95% CI, 0.42-0.83), and when insertion was performed by a nurse (aOR 0.33; 95% CI, 0.22-0.50). CONCLUSION: PPIUD has low complication rates and can be safely inserted by a variety of trained health staff. Given the immediate benefit of the one-stop approach, governments should urgently consider adopting this model
Induction of humoral immune response to multiple recombinant Rhipicephalus appendiculatus antigens and their effect on tick feeding success and pathogen transmission
BACKGROUND: Rhipicephalus appendiculatus is the primary vector of Theileria parva, the etiological agent of East Coast fever (ECF), a devastating disease of cattle in sub-Saharan Africa. We hypothesized that a vaccine targeting tick proteins that are involved in attachment and feeding might affect feeding success and possibly reduce tick-borne transmission of T. parva. Here we report the evaluation of a multivalent vaccine cocktail of tick antigens for their ability to reduce R. appendiculatus feeding success and possibly reduce tick-transmission of T. parva in a natural host-tick-parasite challenge model.
METHODS: Cattle were inoculated with a multivalent antigen cocktail containing recombinant tick protective antigen subolesin as well as two additional R. appendiculatus saliva antigens: the cement protein TRP64, and three different histamine binding proteins. The cocktail also contained the T. parva sporozoite antigen p67C. The effect of vaccination on the feeding success of nymphal and adult R. appendiculatus ticks was evaluated together with the effect on transmission of T. parva using a tick challenge model.
RESULTS: To our knowledge, this is the first evaluation of the anti-tick effects of these antigens in the natural host-tick-parasite combination. In spite of evidence of strong immune responses to all of the antigens in the cocktail, vaccination with this combination of tick and parasite antigens did not appear to effect tick feeding success or reduce transmission of T. parva.
CONCLUSION: The results of this study highlight the importance of early evaluation of anti-tick vaccine candidates in biologically relevant challenge systems using the natural tick-host-parasite combination
Evidence for conservation in antigen gene sequences combined with extensive polymorphism at VNTR loci
Theileria parva is a tick‐transmitted apicomplexan protozoan parasite that infects lymphocytes of cattle and African Cape buffalo (Syncerus caffer), causing a frequently fatal disease of cattle in eastern, central and southern Africa. A live vaccination procedure, known as infection and treatment method (ITM), the most frequently used version of which comprises the Muguga, Serengeti‐transformed and Kiambu 5 stocks of T. parva, delivered as a trivalent cocktail, is generally effective. However, it does not always induce 100% protection against heterologous parasite challenge. Knowledge of the genetic diversity of T. parva in target cattle populations is therefore important prior to extensive vaccine deployment. This study investigated the extent of genetic diversity within T. parva field isolates derived from Ankole (Bos taurus) cattle in south‐western Uganda using 14 variable number tandem repeat (VNTR) satellite loci and the sequences of two antigen‐encoding genes that are targets of CD8+T‐cell responses induced by ITM, designated Tp1 and Tp2. The findings revealed a T. parva prevalence of 51% confirming endemicity of the parasite in south‐western Uganda. Cattle‐derived T. parva VNTR genotypes revealed a high degree of polymorphism. However, all of the T. parva Tp1 and Tp2 alleles identified in this study have been reported previously, indicating that they are widespread geographically in East Africa and highly conserved
Evaluation of PCR for direct detection of mycobacterium tuberculosis complex in sputum samples in Kampala, Uganda
Objective: The aim of this study was to evaluate an in-house PCR for direct detection of Mycobacterium tuberculosis complex (MTC) in sputum samples.Design: Across sectional study was conducted on samples isolates from suspected TB patients. Settings: Patients presenting to Mulago hospital Ward 5 TB Clinics for management and care from June 2014 to April 2015. Subjects: Three sputum samples per patient were obtained from 30 patients with negative (N= 90) and 30 patients with positive (N= 90) ZN smear results for a total of 180 sputum samples was studied. The samples were processed using N-acetyl-L-cycteine and 4% NaOH. Genomic DNA was extracted from the sputum samples and used as template for IS6110-PCR. The prevalence of MTC bacilli in the sputum samples was determined. Results: IS6l110-PCR detected MTC bacilli in 81% (73/90) sputum samples from patients with ZN-positive smears while it detected 51% (46/ 90) sputum samples from patients with ZN-negative. There were statistically significant associations between frequency in performing PCR on three sputum samples per patient and increased proportion of samples positive for MTC, p<0.05). All the 30 patients with ZN positive smears were positive on IS6110-PCR, while 80% (24/30) patients with ZN-negative smears were positive on IS6110-PCR. Chi square test revealed a statistically significant positive association between ZN positive and ZN-negative smears p<0.05. Conclusion: In low income setting burden with high TB incidence and mortality, inhouse IS6110-PCR efficiently detects MTC bacilli in sputum samples and can be introduced for routine detection of these bacilli in isolates form pulmonary TB suspects
Effect Of Seasonal Rainfall And Other Environmental Changes, On Snail Density And Infection Rates With Schistosoma mansoni Fifteen Years After The Last Snails\' Study In Kigungu, Entebbe, Uganda
Background: The last study on snail population density in relation to rainfall pattern in Kigungu canoe landing and recreational sites on Lake Victoria shore was earlier
carried out about fifteen years ago. This study also reviewed the influence of other
environmental factors on the snails\' infection rate.
Objective: To reassess the density dynamic of Biomphalaria (B) choanomphala and
Biomphalaria (B) pfeifferi, which act as the intermediate host for S. mansoni and
Bulinus (B) globosus, and Bulinus (B) tropicus, which act as intermediate host for S.
haematobium.
Design: Retrospective study.
Setting: Busy canoe landing sites along Lake Victoria in Kigungu fishing village were
selected for the snail sampling.
Results: Nine thousand one hundred and ninety four B. choanomphala were collected
over the study period. The numbers of B. choanomphala collected in each year was 4742
(51.6%) and 4452 (48.4%) in 2004 and 2005 respectively. Of the 4742 B.Choanomphala
collected in 2004, 82 (1.7%) shed human cercariae and 329 (6.7%) shed non-human
cercariae. Whereas in 2005, out of 4452 B. choanomphala collected 302 (6.85%) shed
non-human cercariae and 82 (1.8%) shed human cercariae. Similarly, 4173 B. pfeifferi
were also collected in the same period. Out of which 2224 (53.3%) were collected in
2004 and 1949 (46.7%) in 2005. For B. pfeifferi, 42 (1.9%) out of 2224 snails collected in
2004 shed human cercariae and 246 (11.1%) shed non-human cercariae. While in 2005,
33 out of 1949 snails (1.7%) shed human cercariae and 159 (8.2%) shed non-human
cercariae. Other snails of medical importance collected included 292 B. globosus
and 3094 B. tropicus. None of the Bulinus spp. collected shed any human cercariae
but 37 (2.1%) and 30 (2.3%) B. tropicus shed non-human cercariae in 2004 and 2005
respectively. In 2004 and 2005, the area received, 1729mm and 1959mm of rainfall
respectively. The mean rainfall during the year was 144.05 mm and 163.3 mm in 2004
and 2005 respectively. There was a negative correlation between rainfalls and snail
density dynamic.
Conclusion: We have found in this study that in spite of the bush clearing of the
papyrus swamps which originally was the major habitats for B. choanomphala, B.
pfeifferi and the Bulinus spp the intermediate host for schistosome at all canoe landing
sites at Kigungu, these snails are still present. Moreover, that their population density
dynamic and infection rate are inversely proportional to the rainfall pattern. East African Medical Journal Vol. 85 (11) 2008: pp. 556-56
Vaccination against Bm86 Homologues in Rabbits Does Not Impair Ixodes ricinus Feeding or Oviposition
Human tick-borne diseases that are transmitted by Ixodes ricinus, such as Lyme
borreliosis and tick borne encephalitis, are on the rise in Europe.
Diminishing I. ricinus populations in nature can reduce tick exposure to
humans, and one way to do so is by developing an anti-vector vaccine against
tick antigens. Currently, there is only one anti-vector vaccine available
against ticks, which is a veterinary vaccine based on the tick antigen Bm86 in
the gut of Rhipicephalus microplus. Bm86 vaccine formulations cause a
reduction in the number of Rhipicephalus microplus ticks that successfully
feed, i.e. lower engorgement weights and a decrease in the number of
oviposited eggs. Furthermore, Bm86 vaccines reduce transmission of bovine
Babesia spp. Previously two conserved Bm86 homologues in I. ricinus ticks,
designated as Ir86-1 and Ir86-2, were described. Here we investigated the
effect of a vaccine against recombinant Ir86-1, Ir86-2 or a combination of
both on Ixodes ricinus feeding. Recombinant Ixodes ricinus Bm86 homologues
were expressed in a Drosophila expression system and rabbits were immunized
with rIr86-1, rIr86-2, a combination of both or ovalbumin as a control. Each
animal was infested with 50 female adults and 50 male adults Ixodes ricinus
and tick mortality, engorgement weights and egg mass were analyzed. Although
serum IgG titers against rIr86 proteins were elicited, no effect was found on
tick feeding between the rIr86 vaccinated animals and ovalbumin vaccinated
animals. We conclude that vaccination against Bm86 homologues in Ixodes
ricinus is not an effective approach to control Ixodes ricinus populations,
despite the clear effects of Bm86 vaccination against Rhipicephalus microplus
Technique of re-hilling sweetpotato mounds to reduce Cylas spp. weevil infestation and improve sweetpotato yield in Soroti district, North Eastern Uganda
Cylas brunneus and C. puncticollis (Coleoptera: Apionidae) are the economic pests of sweetpotato in Uganda and contribute to low crop yield and quality. On-farm work was done in Soroti district, a major sweetpotato growing area, to test integrated crop management (ICM) techniques to improve yield and reduce weevil damage. Two ICM components were evaluated, that is, improved varieties and re-hilling of mounds. The latter treatment was applied to cover cracks, the entry points that weevils use for accessing storage roots. Yield of improved varieties, namely, NASPOT 1 and 1927, compared favorably with that of the control variety, Haraka. In general, re-hilling treatment resulted into significant crop yield increment and low weevil attack on most of the test materials. Results showed that spot re-hilling done when soil cracks appear was sufficient for reducing weevil infestation
Knowledge, attitudes and practices of prevention of mother to child transmision of HIV among women in Laroo Division Gulu Municipality, Uganda
This study is exploring the knowledge, attitudes and practices of Prevention of Mother to Child Transmission (PMTCT) of Human Immunodeficiency Virus (HIV) among child bearing women aged between 15- 45 years old in Laroo division in Gulu municipality. The goal of the study was to determine the level of attitude as well as of knowledge and belief about PMTCT and proportion of women practicing it among the child bearing women of Laroo Division. The Cross-sectional and Descriptive study design was applied in multistage sampling method with random selection of a parish followed by random selection of a village within the parish from which a sample of homesteads was randomly selected. From each homesteads, a single respondent was randomly selected and registered in the study. Questionnaires were given to respondents that had consented to take part in the study. A total of 208 respondents were registered and interviewed in a period of February to march 2011. There were 165 (79.3%) of the mothers who had knowledge about various PMTCT methods. Of these 86(52%) heard about PMTCT first from hospital. 50 (30%) knew about exclusive breast feeding, while another 50(30%) use of ART, 45(27%) knew about replacement feedings and only 21(13%) knew of elective caesarean section as method of PMTCT. However the majority of the mothers 159(96.5%) thought that PMTCT was beneficial. Nevertheless some mothers thought that PMTCT causes various counter indications including infertility 17 (10.5%) and abnormalities in children at birth 27 (16.7). Their HIV serostatus also varied. Of the 135(81.7%) screened for HIV 42(31.2%) tested HIV positive and only 27 (64.2%) used contraceptives to prevent pregnancy while they were HIV positive. However of the correspondents who tested positive in their last HIV tests, the majority (83%) had had at least a pregnancy after testing HIV positive of which 6.8% did not practice PMTCT. Our study suggests evidence that Knowledge, attitude and practice of PMTCT among women of reproductive age in Laroo Division in Gulu municipality in Northern Uganda is adequate.Nevertheless with the infection rate of 31.2% among them points out that there is a substantial burden of HIV in the women community
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