91 research outputs found
Provider-initiated HIV testing and counseling in Mbeya City, south-western Tanzania: knowledge and practice of health care providers
Provider-initiated testing and counseling (PITC) is a routine HIV counseling and testing offered to adult clients attending at health care facilities. In Tanzania PITC started in 2007, with the aim of increasing early HIV diagnosis and timely access to care, treatment and support services. The objective of this study was to assess the level of knowledge and practice of health care providers on PITC. This cross sectional study was conducted in April-May 2010 among nurses and clinicians working in the government health care facilities in Mbeya City, south-western Tanzania. Self-administered questionnaire was used to obtain relevant information from the study participants. A total of 402 (95% response rate) care providers were interviewed. Their mean (± SD) age was 41 ± 9.5 years. The majority 304 (76%) were nurses. Their duration of practice ranged from 4 months to 39 years. All the care providers reported to be aware of PITC services. However, 35% of them had inadequate knowledge of PITC and 269 (67%) reported to have ever offered PITC services. Median number of clients attended per week was 3 (IQR, 1-6 clients). Participants who had attended special training on PITC were 6-fold more likely to offer PITC services [OR = 6.2, 95% CI = 3.7-10.2; P<0.001] than those who had not attended. In conclusion more than one-third of health providers do not routinely offer PITC in Mbeya City, leading to missed opportunity for early HIV diagnosis. On job and in-service training to improve PITC knowledge and supportive supervision for those trained is required
Longitudinal evaluation of Ocimum and other plants effects on the feeding behavioral response of mosquitoes (Diptera: Culicidae) in the field in Tanzania
<p>Abstract</p> <p>Background</p> <p>The use of repellent materials from plants against nuisance insects is common with great potential to compliment existing malaria control programmes and this requires evaluation in the field. Ocimum plant species, <it>Ocimum suave </it>(Willd) and <it>O. kilimandscharicum </it>(Guerke) materials and their essential oils extracted by steam distillation were evaluated in the field and experimental huts for repellence, exophily and feeding inhibition effects against three mosquito species, <it>Anopheles arabiensis </it>(Patton), <it>An. gambiae </it>ss (Giles) and <it>Culex quinquefasciatus </it>(Say). The protective effect of essential oils from Ocimum plants were compared with N, N-diethly-3- methylbenzamide (DEET), a standard synthetic repellent. Also, the protective effect of fumigation by burning of repellent plants; <it>Ocimum suave, Ocimum kilimandscharicum</it>, <it>Azadirachta indica</it>, <it>Eucalyptus globules </it>and <it>Lantana camara </it>were tested in experimental huts and selected local houses.</p> <p>Results</p> <p>In the field, protection by Ocimum plants from mosquito bites was high and there was small variation among different mosquito species. Protection efficiency was 93.4%, 91.98% and 89.75% for <it>An. arabiensis </it>while for <it>Cx</it>. <it>quinquefaciatus </it>it was 91.30%, 88.65% and 90.50% for DEET, <it>Ocimum suave </it>and <it>O. kilimandscharicum </it>respectively. In the experimental hut, deterrence induced by burning of Ocimum and other plants ranged from 73.1.0% to 81.9% for <it>An. arabiensis </it>and 56.5% to 67.8% for <it>Cx. quinquefaciatus</it>, while feeding inhibition was 61.1% to 100% for <it>An. arabiensis </it>and 50% to 100% for <it>Cx. quinquefaciatus</it>. Evaluations under field conditions confirmed high protective efficacy, enhanced feeding inhibition and house entry inhibition (Deterrence).</p> <p>Conclusion</p> <p>This study shows the potential of <it>Ocimum suave and Ocimum kilimandscharicum </it>crude extracts and whole plants of <it>Ocimum suave, Ocimum kilimandscharicum</it>, <it>Azadirachta indica</it>, <it>Eucalyptus globules and Lantana camara </it>for use in protecting against human biting while the burning of plants reduces significantly the indoor resting mosquitoes.</p
Longitudinal evaluation of Ocimum and other plants effects on the feeding behavioral response of mosquitoes (Diptera: Culicidae) in the field in Tanzania
<p>Abstract</p> <p>Background</p> <p>The use of repellent materials from plants against nuisance insects is common with great potential to compliment existing malaria control programmes and this requires evaluation in the field. Ocimum plant species, <it>Ocimum suave </it>(Willd) and <it>O. kilimandscharicum </it>(Guerke) materials and their essential oils extracted by steam distillation were evaluated in the field and experimental huts for repellence, exophily and feeding inhibition effects against three mosquito species, <it>Anopheles arabiensis </it>(Patton), <it>An. gambiae </it>ss (Giles) and <it>Culex quinquefasciatus </it>(Say). The protective effect of essential oils from Ocimum plants were compared with N, N-diethly-3- methylbenzamide (DEET), a standard synthetic repellent. Also, the protective effect of fumigation by burning of repellent plants; <it>Ocimum suave, Ocimum kilimandscharicum</it>, <it>Azadirachta indica</it>, <it>Eucalyptus globules </it>and <it>Lantana camara </it>were tested in experimental huts and selected local houses.</p> <p>Results</p> <p>In the field, protection by Ocimum plants from mosquito bites was high and there was small variation among different mosquito species. Protection efficiency was 93.4%, 91.98% and 89.75% for <it>An. arabiensis </it>while for <it>Cx</it>. <it>quinquefaciatus </it>it was 91.30%, 88.65% and 90.50% for DEET, <it>Ocimum suave </it>and <it>O. kilimandscharicum </it>respectively. In the experimental hut, deterrence induced by burning of Ocimum and other plants ranged from 73.1.0% to 81.9% for <it>An. arabiensis </it>and 56.5% to 67.8% for <it>Cx. quinquefaciatus</it>, while feeding inhibition was 61.1% to 100% for <it>An. arabiensis </it>and 50% to 100% for <it>Cx. quinquefaciatus</it>. Evaluations under field conditions confirmed high protective efficacy, enhanced feeding inhibition and house entry inhibition (Deterrence).</p> <p>Conclusion</p> <p>This study shows the potential of <it>Ocimum suave and Ocimum kilimandscharicum </it>crude extracts and whole plants of <it>Ocimum suave, Ocimum kilimandscharicum</it>, <it>Azadirachta indica</it>, <it>Eucalyptus globules and Lantana camara </it>for use in protecting against human biting while the burning of plants reduces significantly the indoor resting mosquitoes.</p
Mosquito Abundance, Bed net Coverage and Other Factors Associated with Variations in Sporozoite Infectivity Rates in Four Villages of Rural Tanzania.
Entomological surveys are of great importance in decision-making processes regarding malaria control strategies because they help to identify associations between vector abundance both species-specific ecology and disease intervention factors associated with malaria transmission. Sporozoite infectivity rates, mosquito host blood meal source, bed net coverage and mosquito abundance were assessed in this study. A longitudinal survey was conducted in four villages in two regions of Tanzania. Malaria vectors were sampled using the CDC light trap and pyrethrum spray catch methods. In each village, ten paired houses were selected for mosquitoes sampling. Sampling was done in fortnight case and study was undertaken for six months in both Kilimanjaro (Northern Tanzania) and Dodoma (Central Tanzania) regions. A total of 6,883 mosquitoes were collected including: 5,628 (81.8%) Anopheles arabiensis, 1,100 (15.9%) Culex quinquefasciatus, 89 (1.4%) Anopheles funestus, and 66 (0.9%) Anopheles gambiae s.s. Of the total mosquitoes collected 3,861 were captured by CDC light trap and 3,022 by the pyrethrum spray catch method. The overall light trap: spray catch ratio was 1.3:1. Mosquito densities per room were 96.5 and 75.5 for light trap and pyrethrum spray catch respectively. Mosquito infectivity rates between villages that have high proportion of bed net owners and those without bed nets was significant (P < 0.001) and there was a significant difference in sporozoite rates between households with and without bed nets in these four villages (P < 0.001). Malaria remains a major problem in the study areas characterized as low transmission sites. Further studies are required to establish the annual entomological inoculation rates and to observe the annual parasitaemia dynamics in these communities. Outdoor mosquitoes collection should also be considered
Protective Efficacy of Menthol Propylene Glycol Carbonate Compared to N, N-diethyl-Methylbenzamide Against Mosquito Bites in Northern Tanzania.
The reduction of malaria parasite transmission by preventing human-vector contact is critical in lowering disease transmission and its outcomes. This underscores the need for effective and long lasting arthropod/insect repellents. Despite the reduction in malaria transmission and outcomes in Tanzania, personal protection against mosquito bites is still not well investigated. This study sought to determine the efficacy of menthol propylene glycol carbonate (MR08), Ocimum suave as compared to the gold standard repellent N, N-diethyl-methylbenzamide (DEET), either as a single dose or in combination (blend), both in the laboratory and in the field against Anopheles gambiae s.l and Culex quinquefasciatus. In the laboratory evaluations, repellents were applied on one arm while the other arm of the same individual was treated with a base cream. Each arm was separately exposed in cages with unfed female mosquitoes. Repellents were evaluated either as a single dose or as a blend. Efficacy of each repellent was determined by the number of mosquitoes that landed and fed on treated arms as compared to the control or among them. In the field, evaluations were performed by human landing catches at hourly intervals from 18:00  hr to 01:00  hr. A total of 2,442 mosquitoes were collected during field evaluations, of which 2,376 (97.30%) were An. gambiae s.l while 66 (2.70%) were Cx. quinquefaciatus. MR08 and DEET had comparatively similar protective efficacy ranging from 92% to 100 for both single compound and blends. These findings indicate that MR08 has a similar protective efficacy as DEET for personal protection outside bed nets when used singly and in blends. Because of the personal protection provided by MR08, DEET and blends as topical applicants in laboratory and field situations, these findings suggest that, these repellents could be used efficiently in the community to complement existing tools. Overall, Cx. quinquefasciatus were significantly prevented from blood feeding compared to An. gambiae s.l. The incorporation of these topical repellents for protection against insect bites can be of additional value in the absence or presence of IRS and ITNs coverage. However, a combination of both the physical (bed nets) and the repellent should be used in an integrated manner for maximum protection, especially before going to bed. Additional research is needed to develop repellents with longer duration of protection
Comparative evaluation of four mosquitoes sampling methods in rice irrigation schemes of lower Moshi, northern Tanzania
Adult malaria vector sampling is the most important parameter for setting up an intervention and understanding disease dynamics in malaria endemic areas. The intervention will ideally be species-specific according to sampling output. It was the objective of this study to evaluate four sampling techniques, namely human landing catch, pit shelter, indoor resting collection and odour-baited entry trap. These four sampling methods were evaluated simultaneously for thirty days during October 2008, a season of low mosquitoes density and malaria transmission. These trapping methods were performed in one village for maximizing homogeneity in mosquito density. The cattle and man used in odour-baited entry trap were rotated between the chambers to avoid bias. A total of 3,074 mosquitoes were collected. Among these 1,780 (57.9%) were Anopheles arabiensis and 1,294 (42.1%) were Culex quinquefasciatus. Each trap sampled different number of mosquitoes, Indoor resting collection collected 335 (10.9%), Odour-baited entry trap-cow 1,404 (45.7%), Odour-baited entry trap-human 378 (12.3%), Pit shelter 562 (18.3%) and HLC 395 (12.8%). General linear model univariate analysis method was used, position of the trapping method had no effect on mosquito density catch (DF = 4, F = 35.596, P = 0.78). Days variation had no effect on the collected density too (DF = 29, F = 4.789, P = 0.09). The sampling techniques had significant impact on the caught mosquito densities (DF = 4, F = 34.636, P < 0.0001). The Wilcoxon pair-wise comparison between mosquitoes collected in human landing catch and pit shelter was significant (Z = -3.849, P < 0.0001), human landing catch versus Indoor resting collection was not significant (Z = -0.502, P = 0.615), human landing catch versus odour-baited entry trap-man was significant (Z = -2.687, P = 0.007), human landing catch versus odour-baited entry trap-cow was significant (Z = -3.127, P = 0.002). Odour-baited traps with different baits and pit shelter have shown high productivity in collecting higher densities of mosquitoes than human landing catch. These abilities are the possibilities of replacing the human landing catch practices for sampling malaria vectors in areas with An. arabiensis as malaria vectors. Further evaluations of these sampling methods need to be investigated is other areas with different species
Evaluation of uptake and attitude to voluntary counseling and testing among health care professional students in Kilimanjaro region, Tanzania
<p>Abstract</p> <p>Background</p> <p>Voluntary counseling and testing (VCT) is a corner stone for successful implementation of prevention, care and support services among HIV negative and positive individuals. VCT is also perceived to be an effective strategy in risk reduction among sexually active young people.. This study aimed to assess the acceptability of VCT and its actual uptake among young health care professional students at KCM College of Tumaini University and Allied health schools.</p> <p>Methods</p> <p>This was a cross-sectional study. A structured questionnaire was used among health care professional students aged 18–25 years who were enrolled in degrees, diplomas and certificates courses at Kilimanjaro Christian Medical College and all other Allied health schools</p> <p>Results</p> <p>A total of 309 students were recruited, among these 197 (63.8%) were females. All respondents were aware of the benefits of VCT. Only 107 (34.6%) of students have had VCT done previously. About 59 (19.1%) of the students had negative for health care professional to attend VCT. Risk perception among the students was low (37.2%) even though they were found to have higher risk behaviors that predispose them to get HIV infection.</p> <p>Conclusion</p> <p>Awareness of VCT services and willingness to test is high among students; however its uptake is low. In order to promote these services, a comprehensive training module on VCT needs to be included in their training curricula. In particular, more emphasis should focus on the benefits of VCT and to help the students to internalize the risk of HIV so that they can take preventive measures.</p
Change in Composition of the Anopheles Gambiae Complex and its Possible Implications for the Transmission of Malaria and Lymphatic Filariasis in North-Eastern Tanzania.
A dramatic decline in the incidence of malaria due to Plasmodium falciparum infection in coastal East Africa has recently been reported to be paralleled (or even preceded) by an equally dramatic decline in malaria vector density, despite absence of organized vector control. As part of investigations into possible causes for the change in vector population density, the present study analysed the Anopheles gambiae s.l. sibling species composition in north-eastern Tanzania. The study was in two parts. The first compared current species complex composition in freshly caught An. gambiae s.l. complex from three villages to the composition reported from previous studies carried out 2-4 decades ago in the same villages. The second took advantage of a sample of archived dried An. gambiae s.l. complex specimens collected regularly from a fourth study village since 2005. Both fresh and archived dried specimens were identified to sibling species of the An. gambiae s.l. complex by PCR. The same specimens were moreover examined for Plasmodium falciparum and Wuchereria bancrofti infection by PCR. As in earlier studies, An. gambiae s.s., Anopheles merus and Anopheles arabiensis were identified as sibling species found in the area. However, both study parts indicated a marked change in sibling species composition over time. From being by far the most abundant in the past An. gambiae s.s. was now the most rare, whereas An. arabiensis had changed from being the most rare to the most common. P. falciparum infection was rarely detected in the examined specimens (and only in An. arabiensis) whereas W. bancrofti infection was prevalent and detected in all three sibling species. The study indicates that a major shift in An. gambiae s.l. sibling species composition has taken place in the study area in recent years. Combined with the earlier reported decline in overall malaria vector density, the study suggests that this decline has been most marked for An. gambiae s.s., and least for An. arabiensis, leading to current predominance of the latter. Due to differences in biology and vectorial capacity of the An. gambiae s.l. complex the change in sibling species composition will have important implications for the epidemiology and control of malaria and lymphatic filariasis in the study area
The role of cow urine in the oviposition site preference of culicine and Anopheles mosquitoes
<p>Abstract</p> <p>Background</p> <p>Chemical and behavioural ecology of mosquitoes plays an important role in the development of chemical cue based vector control. To date, studies available have focused on evaluating mosquito attractants and repellents of synthetic and human origins. This study, however, was aimed at seasonal evaluation of the efficiency of cow urine in producing oviposition cues to <it>Anopheles gambiae </it>s.l. and <it>Culex quinquefasciatus </it>in both laboratory and field conditions.</p> <p>Methods</p> <p>Oviposition response evaluation in laboratory conditions was carried out in mosquito rearing cages. The oviposition substrates were located in parallel or in diagonal positions inside the cage. Urine evaluation against gravid females of <it>An. arabiensis </it>and <it>Cx. quinquefasciatus </it>was carried out at Day 1, Day 3 and Day 7. Five millilitres (mls) of cow urine was added to oviposition substrate while de-chlorinated water was used as a control. In field experiments, 500 mls of cow urine was added in artificial habitats with 2500 mls of de-chlorinated water and 2 kgs of soil. The experiment was monitored for thirty consecutive days, eggs were collected daily from the habitats at 7.00 hrs. Data analysis was performed using parametric and non-parametric tests for treatments and controls while attraction of the oviposition substrate in each species was presented using Oviposition Activity Index (OAI).</p> <p>Results</p> <p>The OAI was positive with ageing of cattle urine in culicine species in both laboratory and field experiments. The OAI for anopheline species was positive with fresh urine. The OAI during the rainy season was positive for all species tested while in the dry season the OAI for culicine spp and <it>Anopheles gambiae </it>s.l., changed with time from positive to negative values.</p> <p>Based on linear model analysis, seasons and treatments had a significant effect on the number of eggs laid in habitats, even though the number of days had no effect.</p> <p>Conclusion</p> <p>Oviposition substrates treated with cow urine in both laboratory and field conditions have shown that cow urine left to age from 1-7 days has an influence on oviposition behavioural response in mosquitoes. The analysis of microbial colonies for decaying urine should be investigated along with its associated by-products.</p
Durability associated efficacy of long-lasting insecticidal nets after five years of household use
<p>Abstract</p> <p>Background</p> <p>Long-lasting insecticidal nets (LLINs) have been strongly advocated for use to prevent malaria in sub-Saharan Africa and have significantly reduced human-vector contact. PermaNet<sup>® </sup>2.0 is among the five LLINs brands which have been given full approval by the WHO Pesticide Evaluation Scheme (WHOPES). The LLINs are expected to protect the malaria endemic communities, but a number of factors within the community can affect their durability and efficacy. This study evaluated the durability, efficacy and retention of PermaNet<sup>® </sup>2.0 after five years of use in a Tanzanian community.</p> <p>Method</p> <p>Two to three day- old non blood-fed female mosquitoes from an insectary susceptible colony (<it>An. gambiae </it>s.s, this colony was established at TPRI from Kisumu, Kenya in 1992) and wild mosquito populations (<it>An. arabiensis </it>and <it>Culex quinquefasciatus</it>) were used in cone bioassay tests to assess the efficacy of mosquito nets.</p> <p>Findings</p> <p>The knockdown effect was recorded after three minutes of exposure, and mortality was recorded after 24 hours post-exposure. Mortality of <it>An. gambiae </it>s.s from insectary colony was 100% while <it>An. arabiensis </it>and <it>Cx.quinquefasciatus </it>wild populations had reduced mortality. Insecticide content of the new (the bed net of the same brand but never used before) and used PermaNet<sup>® </sup>2.0 was determined using High Performance Liquid Chromatography (HPLC).</p> <p>Conclusion</p> <p>The results of this study suggest that, in order to achieve maximum protection against malaria, public health education focusing on bed net use and maintenance should be incorporated into the mass distribution of nets in communities.</p
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