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Four p67 alleles identified in South African Theileria parva field samples
No full textPrevious studies characterizing the Theileria parva p67 gene in East Africa revealed two alleles. Cattle-derived isolates associated with East Coast fever (ECF) have a 129bp deletion in the central region of the p67 gene (allele 1), compared to buffalo-derived isolates with no deletion (allele 2). In South Africa, Corridor disease outbreaks occur if there is contact between infected buffalo and susceptible cattle in the presence of vector ticks. Although ECF was introduced into South Africa in the early 20th century, it has been eradicated and it is thought that there has been no cattle to cattle transmission of T. parva since. The variable region of the p67 gene was amplified and the gene sequences analyzed to characterize South African T. parva parasites that occur in buffalo, in cattle from farms where Corridor disease outbreaks were diagnosed and in experimentally infected cattle. Four p67 alleles were identified, including alleles 1 and 2 previously detected in East African cattle and buffalo, respectively, as well as two novel alleles, one with a different 174bp deletion (allele 3), the other with a similar sequence to allele 3 but with no deletion (allele 4). Sequence variants of allele 1 were obtained from field samples originating from both cattle and buffalo. Allele 1 was also obtained from a bovine that tested T. parva positive from a farm near Ladysmith in the KwaZulu-Natal Province. East Coast fever was not diagnosed on this farm, but the p67 sequence was identical to that of T. parva Muguga, an isolate that causes ECF in Kenya. Variants of allele 2 were obtained from all T. parva samples from both buffalo and cattle, except Lad 10 and Zam 5. Phylogenetic analysis revealed that alleles 3 and 4 are monophyletic and diverged early from the other alleles. These novel alleles were not identified from South African field samples collected from cattle; however allele 3, with a p67 sequence identical to those obtained in South African field samples from buffalo, was obtained from a Zambian field isolate of a naturally infected bovine diagnosed with ECF. The p67 genetic profiles appear to be more complex than previously thought and cannot be used to distinguish between cattle- and buffalo-derived T. parva isolates in South Africa. The significance of the different p67 alleles, particularly the novel variants, in the epidemiology of theileriosis in South Africa still needs to be determined
Reproductive health services for refugees by refugees: an example from Guinea
No full textThe need to involve refugees in their own reproductive health (RH) services has long been recognised, but there is a lack of published examples describing how this can be achieved collaboratively between refugee initiatives, UNHCR, bilateral development organisations and international relief agencies. This paper outlines the work, outputs and lessons learnt of the Reproductive Health Group (RHG), an organisation of Liberian and Sierra Leonean refugee midwives and laywomen providing RH services to fellow refugees in Guinea's Forest Region between 1996 and 2000. Working as part of the Guinean health system, RHG midwives and community facilitators helped make the RH services in their region the most effective in Guinea at the time. Looking at RHG's achievements, the challenges it faced and partly overcame, it is argued that refugee organisations can plan and implement RH services for refugees where UNHCR and its international partners ensure that they receive funding and technical assistance
Community health insurance amidst abolition of user fees in Uganda: the view from policy makers and health service managers
No full textBACKGROUND: This paper investigates knowledge of Community Health Insurance (CHI) and the perception of its relevance by key policy makers and health service managers in Uganda. Community Health Insurance schemes currently operate in the private-not-for-profit sector, in settings where church-based facilities function. They operate in a wider policy environment where user fees in the public sector have been abolished. METHODS: Semi-structured interviews were conducted during the second half of 2007 with District Health Officers (DHOs) and senior staff of the Ministry of Health (MOH). The qualitative data collected were analyzed using the framework method, facilitated by EZ-Text software. RESULTS: There is poor knowledge and understanding of CHI activities by staff of the MOH headquarters and DHOs. However, a comparison of responses reveals a relatively high level of awareness of CHI principles among DHOs compared to that of MOH staff. All the DHOs in the districts with schemes had a good understanding of CHI principles compared to DHOs in districts without schemes. Out-of-pocket expenditure remains an important feature of health care financing in Uganda despite blanket abolition of user fees in government facilities. CONCLUSION: CHI is perceived as a relevant policy option and potential source of funds for health care. It is also considered a means of raising the quality of health care in both public and private health units. To assess whether it is also feasible to introduce CHI in the public sector, there is an urgent need to investigate the willingness and readiness of stakeholders, in particular high level political authorities, to follow this new path. The current ambiguity and contradictions in the health financing policy of the Uganda MOH need to be addressed and clarified
Update on the efficacy, effectiveness and safety of artemether-lumefantrine combination therapy for treatment of uncomplicated malaria
No full textArtemether–lumefantrine is one of the artemisisnin-based combination therapies
recommended for treatment of uncomplicated falciparum malaria. The drug combination is
highly efficacious against sensitive and multidrug resistant falciparum malaria. It offers the
advantage of rapid clearance of parasites by artemether and the slower elimination of residual
parasites by lumefantrine. The combination can be used in all populations except pregnant
mothers in the first trimester where safety is still uncertain. There are still concerns about safety
and pharmacokinetics of the drug combination in children, especially infants, pregnant mothers
and drug interactions with mainly non-nucleoside reverse transcriptase inhibitors and protease
inhibitors used for HIV therapy
Comparative study of kala-azar vector control measures in eastern Nepal
No full textThis study was conducted to explore the most effective vector control tool among indoor residual spraying (IRS), long lasting insecticidal nets (LLINs) and ecological vector management (EVM) as a part of the regional visceral leishmaniasis elimination initiative. Alpha-cypermethrin as IRS, PermaNet as LLINs and plastering the inner walls of houses with lime as EVM were the interventions. One baseline and three follow-up entomological surveys were carried out in all arms using CDC miniature light traps (LT) and mouth aspirators. Comparisons were made between intervention arms and control arms with pre-intervention and post-intervention vector densities. Light traps were found more efficient in the collection of Phlebotomus argentipes in comparison with aspiration. Vector densities were significantly low in both IRS arm (p=0.009 in LT and p<0.001 in aspirator collections) and LLIN arm (p=0.019 in LT and p=0.023 in aspirator collections) in comparison with control arm. However, in EVM arm, there was no significant difference in P. argentipes sand fly density in comparison with control arm (p=0.785) in LT collections in follow-up surveys. Hence, IRS was found most effective control measure to decrease vector density. LLINs were also found effective and can be considered as a promising alternative vector control tool in VL elimination initiative. Copyright 2009 Elsevier B.V. All rights reserved
Lack of resistance against the tick Ixodes ricinus in two related passering bird species
No full textAlthough many wild bird species may act as reservoir hosts for tick-transmitted diseases and/or support long-distance dispersal of infected ticks, to date no research has been done on the extent to which songbirds may acquire resistance to ixodid ticks. Here we investigate whether two passerine species belonging to the family Paridae, the blue tit (Cyanistes caeruleus) and the great tit (Parus major), are able to acquire resistance after repeated infestations with Ixodes ricinus nymphs. As blue tits are less frequently exposed to I. ricinus in the wild than great tits, we expected I. ricinus to be less adapted towards the blue tit's resistance mechanisms. Over the three infestation sessions we observed consistently high tick attachment rates and yields, high engorgement weights, and short engorgement and moulting durations, indicating that neither of the two songbird species is able to mount effective immune responses against I. ricinus nymphs after repeated infestations. As a consequence of the lack of resistance, birds were unable to prevent the direct harm (acute blood depletion) caused by tick feeding. Birds compensated the erythrocyte loss without reduction in general body condition (body mass corrected for tarsus length). The lack of resistance suggests that I. ricinus has a long co-evolutionary history with both avian hosts, which enables the tick to avoid or suppress the host's resistance responses. 2009 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved
Do behavioural differences help to explain variations in HIV prevalence in adolescents in sub-Saharan Africa?
No full textObjective To compare adolescent risk factors for HIV infection in two countries with high adolescent HIV prevalence and two lower prevalence countries with the aim of identifying risk factors that may help explain differences in adolescent HIV prevalence. Methods Data were available from two nationally representative surveys (South Africa, Zimbabwe), two behavioural intervention trials (Tanzania, Zimbabwe) and one population-based cohort (Uganda). Data on variables known or postulated to be risk factors for HIV infection were compared. Results Few risk behaviours were markedly more common in the high HIV prevalence populations. Risk factors more common in high HIV prevalence settings were genital ulcers and discharge, and women were more likely to report older male partners. Discussion Age mixing may be an important determinate of HIV prevalence in adolescents. Potential reasons for the general lack of association between other adolescent risk factors and adolescent HIV prevalence include adult HIV prevalence, misreported behaviour, different survey methods and other unmeasured adolescent behaviours. If adult factors dominate adolescent HIV risk, it would help explain the failure of behavioural interventions targeted at adolescents and suggests future interventions should include adults
Diversity of life-threatening complications due to Mediterranean spotted fever in returning travelers
No full textBackground. Mediterranean spotted fever (MSF) is a tick-borne infection caused by Rickettsia conorii conorii mainly endemic in the Mediterranean Basin. Although usually considered as a benign disease, severe forms of MSF have been sporadically reported.
Methods. We report on three patients who developed severe MSF complications after a stay in Morocco. Literature was reviewed to assess the frequency and pattern of MSF complications in the largest reported case series in endemic countries.
Results. Each of our three patients diagnosed with MSF presented with a different complicated course: one with meningoencephalitis, one with lung embolism and one with septic shock and multi organ failure. In published series, rate of complications (defined as severe organ involvement) ranged from 1% to 20%. However, study designs and settings were highly variable and did not allow for relevant comparisons. Meningoencephalitis and shock with multi organ failure were the most frequently observed complications. Mortality of severe course was up to 20% in some series.
Conclusion. Severe organ involvement is not infrequent in patients with Mediterranean spotted fever and fatal outcome is regularly reported. Because presentations of complicated course may be extremely diverse, a high index of suspicion is required in febrile patients with potential exposure, in particular if skin rash and/or eschar are found. Early appropriate antibiotherapy is crucial to improve outcome
Immune reconstitution inflammatory syndrome in patients starting antiretroviral therapy for HIV infection: a systematic review and meta-analysis
No full textIn patients with HIV-1 infection who are starting combination antiretroviral therapy (ART), the incidence of immune reconstitution inflammatory syndrome (IRIS) is not well defined. We did a meta-analysis to establish the incidence and lethality of the syndrome in patients with a range of previously diagnosed opportunistic infections, and examined the relation between occurrence and the degree of immunodeficiency. Systematic review identified 54 cohort studies of 13 103 patients starting ART, of whom 1699 developed IRIS. We calculated pooled cumulative incidences with 95% credibility intervals (CrI) by Bayesian methods and did a random-effects metaregression to analyse the relation between CD4 cell count and incidence of IRIS. In patients with previously diagnosed AIDS-defining illnesses, IRIS developed in 37.7% (95% CrI 26.6-49.4) of those with cytomegalovirus retinitis, 19.5% (6.7-44.8) of those with cryptococcal meningitis, 15.7% (9.7-24.5) of those with tuberculosis, 16.7% (2.3-50.7) of those with progressive multifocal leukoencephalopathy, and 6.4% (1.2-24.7) of those with Kaposi's sarcoma, and 12.2% (6.8-19.6) of those with herpes zoster. 16.1% (11.1-22.9) of unselected patients starting ART developed any type of IRIS. 4.5% (2.1-8.6) of patients with any type of IRIS died, 3.2% (0.7-9.2) of those with tuberculosis-associated IRIS died, and 20.8% (5.0-52.7) of those with cryptococcal meningitis died. Metaregression analyses showed that the risk of IRIS is associated with CD4 cell count at the start of ART, with a high risk in patients with fewer than 50 cells per microL. Occurrence of IRIS might therefore be reduced by initiation of ART before immunodeficiency becomes advanced. 2010 Elsevier Ltd. All rights reserved
