Thesis (M.Sc.(Med.))--University of the Witwatersrand, Faculty of Health Sciences, 2013.

A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science in Biology and Control of African Disease Vectors. Johannesburg, February 2012 / In Tanzania both Anopheles funestus and An. gambiae s.l. play a role as major vectors of malaria. Different species exist in the An. funestus group and the An. gambiae complex and play different roles in disease transmission. For malaria vector control programmes knowledge of vector species and their behaviour is key. A recent report on increased exophagy of An. funestus in southern rural Tanzania as a response to increased use of insecticide treated bed nets raised the question of whether there was misidentification of species and/or behavioural insecticide resistance playing a part. The present study used molecular tools to identify the species and determine human biting rates indoors and outdoors along with development and field evaluation of a new tool for sampling malaria vectors which is more effective than human landing catches. The results showed that the majority (96.2%) of the An. funestus group that were collected were An. funestus s.s. by PCR assay. Also, the exophagic proportion (45.9%) of An. funestus was lower than the endophagic proportion (54.1%), similar to other places in Africa, although in this study the difference was insignificant when untreated bed nets and treated bed nets were used. In addition, there was significant outdoor biting activity early in the evening that could lead to the malaria transmission cycle being unaffected by ITNs. The new trap, “Sticky Bucket Trap”, caught considerably fewer mosquitoes (14.2%) than that caught by human landing catches (85.8%), with statistical significance of P>0.05. These results imply that the sticky bucket trap is not a suitable substitute for human landing catches and some modifications are needed to make it more effective. Whereas indoor and outdoor proportions insignificant difference in feeding preference imply that both indoor and outdoor interventions should be used to control this vector.

In order to employ the Sterile Insect Technique (SIT), biologically fit mosquitoes able to compete with their wild counterparts, suitable field sites for mass release of sterilized male mosquitoes, and appropriate methods of rearing genetic sex-separation (GSS) mosquito strains are required. The life history traits and biological fitness of four laboratory-reared, southern African Anopheles arabiensis strains were investigated. Despite being colonized at different times, the four strains demonstrated comparable levels of biological fitness. Three sites in the Kruger National Park were assessed as possible SIT field sites. Mosquito collections were conducted at each site during three summer months. Anopheles arabiensis was predominant at Malahlapanga during each collection period, establishing Malahlapanga as the most appropriate site for SIT field trials. A standard larval diet was shown to be appropriate for rearing An. arabiensis GSS. This work formed the laboratory basis for the evaluation of a SIT strategy for South Africa.

Malaria is transmitted by the mature, blood feeding portion of mosquito vector populations. Malaria vector control programs based on indoor residual spraying (IRS) of insecticides are designed to target resting adult Anopheles mosquitoes before or after they have blood fed. When a female mosquito acquires a blood meal, she could also ingest harmful xenobiotics that are present in the blood. During the resting period after feeding, many processes are initiated in order to assist in the digestion and assimilation of the blood. Ultimately, this enables the mosquito to absorb those amino acids needed for the biosynthesis of yolk proteins, which are essential for subsequent egg maturation. Since the regulation of xenobiotic (including insecticides) detoxification enzyme systems is likely to be altered in response to the ingestion of blood, this study aimed to investigate the effect of a blood meal on insecticide tolerance in insecticide resistant and susceptible southern African strains of the major malaria vector Anopheles funestus. Through the use of CDC bottle bioassays it was demonstrated that blood fed An. funestus carrying a pyrethroid resistant phenotype are even more tolerant of pyrethroid intoxication than their unfed counterparts. Using another major malaria vector, An. gambiae, microarray analysis revealed that a general increase in delta class glutathione-s-transferase (GST) expression occured in response to a blood meal. One gene, GSTD3, was over-expressed in both blood fed An. gambiae and An. funestus. Although this gene could not be validated with real time quantitative PCR, it serves as a viable target for future investigations. Since the pyrethroid resistant phenotype of southern African An. funestus has been linked to the over-expression of the duplicate copy gene CYP6P9, the expression levels of both copies of this gene were investigated. CYP6P9 and its copy, CYP6P13, showed a small but significant increase in expression in response to a blood meal. The increased expression of these major effect genes in response to blood feeding may be responsible for the increase in insecticide tolerance seen in the bottle bioassays. In an effort to repeat these experiments on wild caught An. funestus, field material was collected from Karonga in northern Malawi. Specimens were morphologically identified as members of the An. funestus group. However, attempts to molecularly identify them to species level failed. Through the use of ITS2 and D3 sequence analysis, cytogenetics and cross mating studies it was possible to conclude that these wild caught specimens were a new species. They have been provisionally named An. funestus-like.

Anopheles funestus is a major vector of malaria in the southern African region. Insecticide resistance to pyrethroid and carbamate insecticides has been recorded in populations of this species in South Africa and Mozambique. This study aimed to determine the relationship between pyrethroid resistance and gene expression of two closely related genes, CYP6P9 and CYP6P13, by age and sex in a resistant strain An. funestus from southern Africa, FUMOZ-R. The insecticide susceptibility assays showed that percentage survival in both FUMOZ-R sexes significantly decreased as age increased. The mRNA expressions of CYP6P9 and CYP6P13 were higher in FUMOZ-R relative to the insecticide susceptible strain (FANG). The expression of permethrin resistance varies with age in An. funestus FUMOZ-R. The results indicate that other genes may also be involved in insecticide resistance. In addition to this, the expression profile of other metabolic genes involved in insecticide resistance was also investigated. A microarray based approach was used to identify genes differentially expressed in FUMOZ-R and FANG. As the full set of detoxification genes in An. funestus are unknown, this study investigated the utility of the An. gambiae detox chip to screen for differentially expressed detoxification genes in An. funestus. After optimization of the hybridisation conditions, over 90% of the probes showed a positive signal. Only three genes were significantly (P<0.001) differentially expressed in the females, CYP6P9, COI and CYP6M7. The same genes were also significantly differentially expressed in the adult males, together with an additional 21 transcripts. The third part of this study investigated the gene expression in the first instar, fourth instar and 3-day old adults in FUMOZ-R using the An. gambiae detox chip. The variation in metabolic enzyme gene transcription at the different developmental stages in An. funestus are not known. The identification of differentially transcribed genes at the different life stages provides some insight into the role and function of these genes. A large number of cytochrome P450s (monooxygenases), esterases, glutathione S-transferases (GSTs) and other additional genes were differentially expressed in all life stages. This study provided vital information regarding genes potentially involved in pyrethroid resistant and is the first to provide metabolic or detoxifying transcription gene information in An. funestus.

A DISSERTATION SUBMITTED TO THE FACULTY OF MEDICINE, UNIVERSITY OF THE WITWATERSRAND, JOHANNESBURG, FR THE DEGREE OF MASTER OF SCIENCE IN MEDICINE. / The influence of iron on the outcome of various infections have been extensively reviewed. Clinical observations suggests that iron deficiency may be protective against malaria. Various researchers have shown that certain iron chelators blocked the proliferation of plasmodium falciparum in vitro and in vivo. (Abbreviation abstract) / Andrew Chakane 2018

A thesis submitted to the Faculty of Science University of the Witwatersrand Johannesburg in fulfillment for the requirements of the degree of Master of Science. 14 May 2015. / Peptidomimetic compounds have been shown to exhibit both anti-HIV and anti-malarial activity. A multicomponent reaction was used to create a library of peptidomimetic compounds with an α-hydroxy-β-amino acid unit. The Passerini reaction between an aldehyde, carboxylic acid and isocyanide was used to prepare compounds containing both ester and amide functionalities. These compounds were then subjected to a deprotection-acyl migration strategy giving rise to the target compounds. This approach, known as the Passerini Amine Deprotection Acyl Migration (PADAM) sequence was successfully used to create a library of novel peptidomimetic compounds. From this library, 22 compounds were tested for activity against HIV and malaria. The Passerini reaction gives rise to a product containing a new stereogenic centre, and as the starting aldehyde used (N-Boc-phenylalaninal) has a stereogenic centre, the products were isolated as a mixture of diastereomers. Our research was also focused on finding ways of influencing the stereoselectivity of the reaction and the separation of the resulting diastereomers. The diastereomeric ratio of the Passerini products was found to be approximately 2:1 for all the reactions performed. This ratio could be modified slightly when using certain carboxylic acids and isocyanides that were either very bulky or had a stereogenic centre. Attempts to enzymatically resolve the diastereomeric products were not successful after trials using a library of 25 lipase enzymes. However, use of preparative HPLC enabled the successful separation of most of the diastereomeric mixtures, affording compounds with high purity. X-ray crystallography enabled us to identify the major diastereomers as having the R,S configuration, whilst the minor diastereomers had the S,S configuration at the two stereogenic centres. A possible explanation for the observed stereoselectivity is based on the Felkin-Anh chelation control model. It suggests that mono-protected amino aldehydes follow a chelation controlled mechanism in nucleophilic addition reactions. Chelation occurs, albeit in the form of hydrogen bonding, between the NH and carbonyl oxygen. The library of compounds was tested for activity against both HIV-1 and malaria. Only three compounds showed moderate activity against the malaria parasite, inhibiting parasitic growth by 37-42% at 5 μM respectively. Significantly, all of the active compounds contained an adamantyl moiety. Unfortunately no anti-HIV activity was seen for any of the compounds tested in the HIV-assay.

Background: Malaria continues to pose a complex public health problem amongst pregnant women in Africa (Schantz-Dunn & Nour 2009; Antwi 2010), accounting for over 90% of the global malaria burden (WHO 2002; Morel et al. 2005; Schantz-Dunn & Nour 2009). However, little is known about the impact of information, education and communication (IEC) strategies in malaria prevention and control among pregnant women in Africa. Aims and Objectives: The study sought to identify: evidence of impact of IEC strategies; feasibility, appropriateness, meaningfulness and effectiveness of the IEC strategies; challenges; best practices and key lessons to inform governments, policymakers, health partners, the academic community, directors, managers of health, frontline health professionals and health educators at institutional and community levels. Moreover, the study aimed to develop a theoretical framework to enhance the understanding of issues related to implementation of IEC strategies. Methods: A mixed method approach was adopted. This consisted of a systematic review of evidence within the African context and an evaluation methodology involving a contextually based survey of Ethiopia, Ghana, Nigeria and Tanzania. The systematic review involved a structured search of relevant databases and websites, and hand search strategies. Three sets of evidence were identified and aggregated using a narrative synthesis approach. A survey questionnaire reflecting the outcomes of the review was sent to health professionals and lay persons in the countries under study. Primary data were analysed using SPSS Version 15.0. Non-parametric tests and sensitivity analyses were conducted to assess the nature of opinions among respondents within and across countries. Findings: 3,440 studies were identified during the systematic review. Out of this number, 57 met the inclusion criteria. Following critical appraisal, 50 studies met the criteria for methodological quality. Ten IEC strategies were identified. These were: Staff training and orientation Advocacy Community mass education campaigns House-to-house sensitisation Health education in health units Visiting places of worship Women’s group meetings Integrated health education campaigns Symbolism versus message delivery Audience segmentation versus information delivery. The survey reveals a high level of awareness of IEC strategies among respondents in the African countries studied. The evidence of impact reported by respondents supported the findings of the systematic review. However, there were some differences, and some concerns still remain regarding the extent of impact. The study suggests that using an IEC strategy implementation equation could enhance the understanding of issues related to implementation of IEC strategies. Implications of the findings are outlined, including implications for professional practice in relation to IEC programme implementation, most especially among nurses and midwives. IEC roles and responsibilities of key actors are also proposed. Conclusions: Despite the challenges of adopting a mixed method approach, the study highlights an important relationship between evidence and practice. This approach also helped to ensure that a comprehensive multiperspective view of IEC strategies was achieved. In designing and implementing IEC programmes, clients must be involved in order to encourage community ownership and programme sustainability. Attitudinal change and commitment is required by all stakeholders in order to achieve and maintain impact on malaria in pregnancy. Finally, while recognising the essence of feasibility, appropriateness and meaningfulness of a given strategy, it is worth noting that the key message from this study is that no one single strategy on its own appears ideal. Therefore, there is the need to pay equal attention to both institutional and community-based strategies. Doing one thing alone will not work; more evidence of impact is required to know what works and in what context.

A medicina de viagem (MV) surgiu em resposta ao crescente deslocamento populacional, com o objetivo de prevenir os agravos à saúde relacionados às viagens. No Brasil teve inicio no final da década de 90, momento em que reformas socioeconômicas levaram a melhorias das condições de vida dos brasileiros. O Núcleo de Medicina do Viajante (NMV), do Instituto de Infectologia Emilio Ribas (IIER), foi o primeiro serviço de atenção à saúde do viajante criado na cidade de São Paulo, em maio de 2000. O presente estudo visa: descrever a população de viajantes que procuraram orientação pré-viagem no Núcleo de Medicina do Viajante (NMV) do Instituto de Infectologia Emilio Ribas (IIER) no período de janeiro de 2006 a dezembro de 2010; descrever as medidas de prevenção recomendadas em relação às doenças infecciosas; descrever as atividades de ensino realizadas e a participação do serviço na discussão de diretrizes em políticas públicas em medicina de viagem. No período estudado, 2744 viajantes procuraram orientação pré-viagem no NMV do IIER. Foram realizados 2836 atendimentos de orientação pré-viagem, 92 viajantes procuraram o serviço mais de uma vez. A faixa etária entre 18 e 34 anos (54,2%), o sexo feminino (51,1%) e grau de educação superior (75,5%) foram as principais características demográficas desses viajantes. Os destinos mais procurados foram: África (24,5%), Europa (21,2%), Ásia (16,6%) e Brasil (19,2%). O turismo (35,7%) e o trabalho (35,7%) foram os motivos de viagem mais referidos. O tempo de permanência menor ou igual a 30 dias foi referido pelos viajantes em que o objetivo de viagem foi o turismo, enquanto os viajantes que referiram o trabalho ou estudo apresentaram maior tempo de permanência (p < 0,001). O meio de transporte mais referido foi o aéreo (62,8%). Os viajantes relataram durante a consulta pré-viagem dificuldade de acesso ao serviço. As fontes de informação mais referidas foram: informação a partir de amigos, indicação por profissional da saúde e mídia eletrônica. As medidas de prevenção recomendadas variaram conforme o destino. O tratamento autoadministrado para diarreia foi mais recomendado aos viajantes com destino à Ásia. As vacinas de febre amarela, poliomielite e antimeningocócica A e C foram mais recomendadas aos viajantes com destino à África, assim como a quimioprofilaxia para malária, que foi recomendada para 26,4% dos viajantes para esse destino. A quimioprofilaxia (QPX) para malária foi recomendada em 10,3% de todas as orientações. Houve diferença com significância estatística na recomendação segundo a finalidade (p < 0,30), o destino (p < 0,001) e a duração da viagem (p < 0,001). Das 422 orientações realizadas aos viajantes com destino ao Brasil, a QPX foi recomendada somente para 30 (7,1%). Dos 2744 viajantes atendidos, 664 (24,2%) relataram pelo menos uma morbidade prévia; 66 (2,4%) eram menores de 10 anos de idade; e 157 (5,7%) tinham 60 anos ou mais. Em relação às atividades de ensino, no período do estudo, 83 médicos residentes estagiaram no NMV e foram orientadas onze monografias de conclusão de residência médica. O NMV participou de 12 reuniões para discussão de diretrizes sobre a saúde do viajante e de iniciativas como a Carta de São Paulo (documento em defesa da saúde do viajante elaborado por acadêmicos e profissionais de saúde participantes do SUS). Da criação da Sociedade Brasileira de Medicina de Viagem e da criação do Comitê Estadual de Saúde do Viajante, pela Secretaria de Estado da Saúde de São Paulo. Essas atividades foram passos decisivos para corroborar a implementação de políticas públicas em saúde do viajante no Brasil / Travel medicine (TM) arose in response to the growing population displacement and its objective is the prevention of health problems related to travel. Began in Brazil in the in the late 1990s, at which socioeconomic reforms have led to improvements in of life of Brazilians. Travel Medicine Center (TMC) at \"Instituto de Infectologia Emilio Ribas\" (IIER) was the first health of traveler service created in São Paulo city in May 2000. The present study aims: to describe the traveler population who sought pre-travel guidance in TMC at IIER from January 2006 to December 2010; to describe the recommended preventive measures to travelers concerned with infectious diseases; to describe the teaching activities performed and the service involvement in debating guidelines about public policies in travel medicine. In the time period studied, a total of 2744 travelers sought pre-travel guidance in TMC of IIER, but 2836 assistances were provided for pre-trip orientation since 92 travelers sought the service more than once. The age group between 18-34 years (54.2%), female (51.1%), and university level degree (75.5%) were the main demographic characteristics. The more popular destinations were: Africa (24.5%), Europe (21.2%), Asia (16.6%) and Brazil (19.2%). Tourism (35.7%) and work (35.7%) were the main purposes of trip for travelers. For tourism purpose travelers would stay 30 or less days, while for work or study they stayed for a longer time (p <0,001). Commercial air travel was the preferred alternative (62.8%). The main sources of information were friends, health professionals, and electronic media. The recommended preventive measures varied according to the destination. The self-treatment for diarrhea was more recommended for travelers to Asia. Vaccination against yellow fever, polio, and anti-meningococcal (A and C) was more recommended for travelers to Africa, as well as chemoprophylaxis (CP) of malaria was recommended for 26.4% of travelers to the same country. The CP of malaria was indicated for 10.3% of all assistances. There was statistically significant difference in the recommendation according to purpose (p < 030), destination (p < 0.001) and trip duration (p < 0.001). From 422 assistances to travelers to Brazil, CP was only recommended for 30 (7.1%) travelers. From the 2744 travelers assisted, 664 (24.2%) reported at least one previous morbidity; 66 (2.4%) were under age 10; and 157 (5.7%) were 60 years or older. During the research period and relating to study activities, 83 residents were interns in TMC, and eleven monographs for completion of the Medical Residency were supervised. TMC participated in 12 meetings to discuss guidelines in travel medicine, and participated in initiatives such as \"Carta de São Paulo\" (a document in defense of traveler health prepared by academics and health professionals participating in the Unified Health System); in the institution of the Brazilian Society of Travel Medicine, and of the São Paulo State Travel Medicine Committee by the Secretariat for Health of São Paulo State. These were decisive steps to support implementation of public policies in traveler health in Brazil

A medicina de viagem (MV) surgiu em resposta ao crescente deslocamento populacional, com o objetivo de prevenir os agravos à saúde relacionados às viagens. No Brasil teve inicio no final da década de 90, momento em que reformas socioeconômicas levaram a melhorias das condições de vida dos brasileiros. O Núcleo de Medicina do Viajante (NMV), do Instituto de Infectologia Emilio Ribas (IIER), foi o primeiro serviço de atenção à saúde do viajante criado na cidade de São Paulo, em maio de 2000. O presente estudo visa: descrever a população de viajantes que procuraram orientação pré-viagem no Núcleo de Medicina do Viajante (NMV) do Instituto de Infectologia Emilio Ribas (IIER) no período de janeiro de 2006 a dezembro de 2010; descrever as medidas de prevenção recomendadas em relação às doenças infecciosas; descrever as atividades de ensino realizadas e a participação do serviço na discussão de diretrizes em políticas públicas em medicina de viagem. No período estudado, 2744 viajantes procuraram orientação pré-viagem no NMV do IIER. Foram realizados 2836 atendimentos de orientação pré-viagem, 92 viajantes procuraram o serviço mais de uma vez. A faixa etária entre 18 e 34 anos (54,2%), o sexo feminino (51,1%) e grau de educação superior (75,5%) foram as principais características demográficas desses viajantes. Os destinos mais procurados foram: África (24,5%), Europa (21,2%), Ásia (16,6%) e Brasil (19,2%). O turismo (35,7%) e o trabalho (35,7%) foram os motivos de viagem mais referidos. O tempo de permanência menor ou igual a 30 dias foi referido pelos viajantes em que o objetivo de viagem foi o turismo, enquanto os viajantes que referiram o trabalho ou estudo apresentaram maior tempo de permanência (p < 0,001). O meio de transporte mais referido foi o aéreo (62,8%). Os viajantes relataram durante a consulta pré-viagem dificuldade de acesso ao serviço. As fontes de informação mais referidas foram: informação a partir de amigos, indicação por profissional da saúde e mídia eletrônica. As medidas de prevenção recomendadas variaram conforme o destino. O tratamento autoadministrado para diarreia foi mais recomendado aos viajantes com destino à Ásia. As vacinas de febre amarela, poliomielite e antimeningocócica A e C foram mais recomendadas aos viajantes com destino à África, assim como a quimioprofilaxia para malária, que foi recomendada para 26,4% dos viajantes para esse destino. A quimioprofilaxia (QPX) para malária foi recomendada em 10,3% de todas as orientações. Houve diferença com significância estatística na recomendação segundo a finalidade (p < 0,30), o destino (p < 0,001) e a duração da viagem (p < 0,001). Das 422 orientações realizadas aos viajantes com destino ao Brasil, a QPX foi recomendada somente para 30 (7,1%). Dos 2744 viajantes atendidos, 664 (24,2%) relataram pelo menos uma morbidade prévia; 66 (2,4%) eram menores de 10 anos de idade; e 157 (5,7%) tinham 60 anos ou mais. Em relação às atividades de ensino, no período do estudo, 83 médicos residentes estagiaram no NMV e foram orientadas onze monografias de conclusão de residência médica. O NMV participou de 12 reuniões para discussão de diretrizes sobre a saúde do viajante e de iniciativas como a Carta de São Paulo (documento em defesa da saúde do viajante elaborado por acadêmicos e profissionais de saúde participantes do SUS). Da criação da Sociedade Brasileira de Medicina de Viagem e da criação do Comitê Estadual de Saúde do Viajante, pela Secretaria de Estado da Saúde de São Paulo. Essas atividades foram passos decisivos para corroborar a implementação de políticas públicas em saúde do viajante no Brasil / Travel medicine (TM) arose in response to the growing population displacement and its objective is the prevention of health problems related to travel. Began in Brazil in the in the late 1990s, at which socioeconomic reforms have led to improvements in of life of Brazilians. Travel Medicine Center (TMC) at \"Instituto de Infectologia Emilio Ribas\" (IIER) was the first health of traveler service created in São Paulo city in May 2000. The present study aims: to describe the traveler population who sought pre-travel guidance in TMC at IIER from January 2006 to December 2010; to describe the recommended preventive measures to travelers concerned with infectious diseases; to describe the teaching activities performed and the service involvement in debating guidelines about public policies in travel medicine. In the time period studied, a total of 2744 travelers sought pre-travel guidance in TMC of IIER, but 2836 assistances were provided for pre-trip orientation since 92 travelers sought the service more than once. The age group between 18-34 years (54.2%), female (51.1%), and university level degree (75.5%) were the main demographic characteristics. The more popular destinations were: Africa (24.5%), Europe (21.2%), Asia (16.6%) and Brazil (19.2%). Tourism (35.7%) and work (35.7%) were the main purposes of trip for travelers. For tourism purpose travelers would stay 30 or less days, while for work or study they stayed for a longer time (p <0,001). Commercial air travel was the preferred alternative (62.8%). The main sources of information were friends, health professionals, and electronic media. The recommended preventive measures varied according to the destination. The self-treatment for diarrhea was more recommended for travelers to Asia. Vaccination against yellow fever, polio, and anti-meningococcal (A and C) was more recommended for travelers to Africa, as well as chemoprophylaxis (CP) of malaria was recommended for 26.4% of travelers to the same country. The CP of malaria was indicated for 10.3% of all assistances. There was statistically significant difference in the recommendation according to purpose (p < 030), destination (p < 0.001) and trip duration (p < 0.001). From 422 assistances to travelers to Brazil, CP was only recommended for 30 (7.1%) travelers. From the 2744 travelers assisted, 664 (24.2%) reported at least one previous morbidity; 66 (2.4%) were under age 10; and 157 (5.7%) were 60 years or older. During the research period and relating to study activities, 83 residents were interns in TMC, and eleven monographs for completion of the Medical Residency were supervised. TMC participated in 12 meetings to discuss guidelines in travel medicine, and participated in initiatives such as \"Carta de São Paulo\" (a document in defense of traveler health prepared by academics and health professionals participating in the Unified Health System); in the institution of the Brazilian Society of Travel Medicine, and of the São Paulo State Travel Medicine Committee by the Secretariat for Health of São Paulo State. These were decisive steps to support implementation of public policies in traveler health in Brazil