Long-term safety of replication-defective smallpox vaccine (MVA-BN) in atopic eczema and allergic rhinitis.

BACKGROUND: Availability of a safe smallpox vaccine may be necessary under certain circumstances. Use of the old life virus vaccine was associated with serious adverse events, particularly in the setting of atopic eczema (AE) and immunodeficiency. Modified virus Ankara (MVA)-BN, a highly attenuated strain of vaccinia virus, was developed for vaccination with improved safety profile. METHODS: A phase 1 study was conducted in 60 subjects without history of smallpox vaccination to gain experience with smallpox vaccination using this strain in healthy and atopic subjects. Healthy subjects, subjects with a history of AE, subjects with mild active AE and subjects with mild allergic rhinitis without AE were equally allocated into four groups. MVA-BN was injected s.c. in a dose of 108 TCID50 twice in a 4-week interval. RESULTS: No serious or unexpected adverse reactions were reported. All subjects experienced mild to moderate pain and redness at the injection site. Dermatologic examinations did not reveal any unfavourable reactions to the study medication, particularly no sign or exacerbation of eczema for as long as 196 days. All subjects seroconverted after two vaccinations and no significant difference in antibody titres between the four different groups was observed. CONCLUSIONS: A good safety profile of the MVA-BN vaccine was shown. The absence of adverse events in subjects with atopic disorders appears promising for the development of a safe smallpox vaccine for patients with AE or other atopic diseases.

Suspected new wave of muscular sarcocystosis in travellers returning from Tioman Island, Malaysia, May 2014.

In May 2014, six patients presented in Germany with a Sarcocystis-associated febrile myositis syndrome after returning from Tioman Island, Malaysia. During two earlier waves of infections, in 2011 and 2012, about 100 travellers returning to various European countries from the island were affected. While the first two waves were associated with travel to Tioman Island mostly during the summer months, this current series of infections is associated with travel in early spring, possibly indicating an upcoming new epidemic.

Infection-induced anaemia: a cross-sectional study of 14,636 German travellers aged 20-49 years.

BACKGROUND: Anaemia is a frequently diagnosed condition which can develop as a consequence of numerous factors, including infectious diseases (IDs). Travelling, especially in sub-/tropical regions, leads to an elevated risk of contracting IDs. The aim of our study was to assess the epidemiological significance of IDs in inducing anaemia among a large cohort of returned travellers. METHODS: This was a cross-sectional study in which data on 17,009 returned travellers aged 20-49 years who consulted the travel medicine clinic of the University of Munich between 1999 and 2011 were retrieved and analysed. RESULTS: Of the returned travellers, 8.3 % (6.0 % of males/10.4 % of females) were diagnosed with anaemia. The prevalence of anaemia was significantly elevated among patients of African (21.4/28.3 %) and Asian (11.6/15.7 %) origin. When the study population was restricted to the 14,636 travellers of German origin, 7.1 % of the returned travellers (4.6/9.6 %) were diagnosed with anaemia. The prevalence was significantly elevated among patients who travelled for >30 days (5.7 of males/10.6 % of females) and for male travellers visiting friends and relatives (7.7 %). However, these correlations were confounded by malaria. The prevalence of anaemia was significantly elevated only among returned travellers diagnosed with malaria (36.1 of males/26.9 % of females) and with symptomatic intestinal Entamoeba histolytica infections (30.0/33.3 %). CONCLUSION: Following the exclusion of confounding by malaria from the statistical analysis, the prevalence of anaemia was found to be significantly elevated among patients of African and Asian origin, and among patients of German origin who had travelled for >30 days, it could be mainly attributable to chronic, long-lasting causes. Although more than 550 travel-associated IDs were assessed in our study, only symptomatic intestinal Entamoeba histolytica infections and, to an even larger extent, malaria were determined to be of epidemiological significance for inducing anaemia among travellers.

Comparative study on infection-induced thrombocytopenia among returned travellers.

BACKGROUND: Thrombocytopenia is a frequent finding among ill returned travellers and may be caused by a large number of different conditions, including infectious diseases specific or typical for tropical and subtropical regions. In order to assess the diagnostic significance of thrombocytopenia we investigated a large cohort of returned travellers. METHODS: This was a comparative study in which data collected on 19,473 returned travellers who consulted the outpatient travel clinic of the the University of Munich Hospital between 1999 and 2009 were analysed. Of these, 732 (3.8%) travellers were diagnosed with thrombocytopenia, and their data were compared with those of the remaining 18,741 travellers with normal platelet counts. RESULTS: Thrombocytopenia was significantly more frequent among patients with malaria (63%), acute human immunodeficiency virus infection (48%), dengue fever/dengue haemorrhagic fever (DF/DHF; 47%), Epstein-Barr virus infectious mononucleosis (23%), paratyphoid/typhoid fever (14%), and rickettsiosis (12%). Malaria and DF/DHF caused 25% of all cases of thrombocytopenia (platelet count <140,000/µl) and 75% of all cases of severe thrombocytopenia (platelet count <30,000/µl). Sex, age, country of origin, duration and type of travel were not significantly correlated with thrombocytopenia. The most frequent travel destinations were Asia (42%), Africa (33%), and Latin America (14%). Travellers to Sub-Saharan Africa (high risk for malaria) and to South/South-east Asia (high risk for DF/DHF) had the highest relative risk for thrombocytopenia. CONCLUSION: Platelet count among returned travellers is an essential screening parameter, as thrombocytopenia is highly correlated with important infectious diseases, particularly with malaria and DF/DHF.

Infectious diseases among travellers and migrants in Europe, EuroTravNet 2010.

To investigate trends in travel-associated morbidity with particular emphasis on emerging infections with the potential for introduction into Europe, diagnoses of 7,408 returning travellers presenting to 16 EuroTravNet sites in 2010 were compared with 2008 and 2009. A significant increase in reported Plasmodium falciparum malaria (n=361 (6% of all travel-related morbidity) vs. n=254 (4%) and 260 (5%); p<0.001), P. vivax malaria (n=51 (1%) vs. n=31 (0.5%) and 38 (1%); p=0.027) and dengue fever (n=299 (5%) vs. n=127 (2%) and 127 (2%); p<0.001) was observed. Giardia lamblia was identified in 16% of patients with acute diarrhoea, with no significant annual variation. The proportion of acute diarrhoea due to Campylobacter increased from 7% in 2008 to 12% in 2010 (p=0.001). We recorded 121 patients with pulmonary tuberculosis in 2010, a threefold increase in the proportionate morbidity from 2008 to 2010. In 2010, 60 (0.8%) cases of chronic Chagas disease, 151 (2%) cases of schistosomiasis and 112 (2%) cases of cutaneous larva migrans were reported. Illness patterns in sentinel travellers, captured by EuroTravnet, continue to highlight the potential role of travellers in the emergence of infectious diseases of public health concern in Europe and the relevance of offering medical travel advice and enforcing specific and adequate prophylaxis.

Skin disorders among travellers returning from tropical and non-tropical countries consulting a travel medicine clinic.

OBJECTIVE: To evaluate the causes and risks for imported skin disorders among travellers. METHODS: Data of 34,162 travellers returning from tropical and non-tropical countries and presenting at the outpatient travel medicine clinic of the University of Munich, Germany, between 1999 and 2009 were analyzed for this study. Of these, 12.2% were diagnosed with skin disorders. RESULTS: Main destinations visited were Asia (40%), Africa (27%) and Latin America (21%). Tourism in the form of adventure travel/backpacking (47%) and package holidays (23%) was the most common purpose of travel. The leading causes of skin disorders were arthropodal (23%), bacterial (22%), helminthic (11%), protozoan (6%), viral (6%), allergic (5%) and fungal (4%). The 10 most frequently diagnosed specific skin diseases associated with specific destinations were insect bites (17%, Southern Europe), cutaneous larva migrans (8%, Asia and Latin America), cutaneous leishmaniasis (2.4%, Mediterranean Region/Middle East), dengue fever (1.5%, Asia), rickettsioses (1.3%, Southern Africa), myiasis (0.8%, Central America), filarioses (0.7%, Africa), tick bites (0.6%, Central/Eastern Europe), schistosomiasis (0.6%, Africa) and tungiasis (0.6%, Africa). Travellers in sub-Saharan Africa had the highest relative risk of acquiring skin disorders. CONCLUSION: As more than 20% of all skin disorders among returned travellers were caused by arthropods and about 50% by infectious pathogens, pre-travel consultations should include specific prophylaxis and consider the most important risk factor for the travel destination.

Hepatitis A booster vaccination: is there a need?

Hepatitis A is one of the most common vaccine-preventable infectious diseases in the world. Effective vaccines against hepatitis A have been available since 1992, and they provide long-term immunity against the infection. However, there is no worldwide consensus on how long protection will last or whether there will be a need for hepatitis A virus (HAV) booster vaccinations in the future. In most countries, booster-vaccination policy is guided by manufacturers' recommendations, national authorities, or both. In June, 2002, a panel of international experts met to review the long-term immunogenicity and protection conferred by HAV vaccine in different population groups. Data have shown that after a full primary vaccination course, protective antibody amounts persist beyond 10 years in healthy individuals, and underlying immune memory provides protection far beyond the duration of anti-HAV antibodies. The group concluded that there is no evidence to lend support to HAV booster vaccination after a full primary vaccination course in a healthy individual. However, further investigations are needed before deciding if boosters can be omitted in special patient-groups.

Cost reduction of unlinked testing for anti-HIV by investigation of pooled sera.

Anti-HIV-1 testing of pooled sera was found to be an excellent method of considerably reducing the costs and workload of public health surveillance programmes without the loss of important information. All 54 sera found anti-HIV-1 positive in diagnostic testing and 61 out of 70 sera (87%) found positive in surveillance studies were detected when tested at a dilution of 1:10 with anti-HIV-1-negative human sera. This acceptable loss of sensitivity could be reduced further by lowering the cut-off at which single sera of pools were tested: 96% of the above 70 anti-HIV-1-positive sera were detected. During testing of 618 pools containing 6180 sera from a low-risk population, lowering of the cut-off increased the number of pools with testing of individual sera from five (containing one confirmable anti-HIV-1-positive serum each) to only six (containing no anti-HIV-1-positive serum). Therefore, testing of pooled sera from a low-prevalence population group reduced the costs of testing about ninefold and technician time by about 25-50%.

Estimating the number of HIV transmissions through reused syringes and needles in the Mbeya Region, Tanzania.

OBJECTIVE: HIV infection attributable to medical injections is suspected to be low, although case-control studies have not provided definite results. This study aims to determine the number of HIV infections caused by the reuse of syringes and needles in the Mbeya Region, Tanzania. METHODS: The direct identification or detection of HIV in syringes and needles under field conditions was not appropriate, therefore a surrogate marker consisting of two components for possible HIV transmission was used: insufficient sterilization, and blood remaining from a previous patient. The assumption was that HIV infection can only occur if both markers are positive. Samples were collected in nine health-care facilities. All syringes and needles prepared for use in these facilities were collected without prior notification. The samples were rinsed and the resulting fluid was cultured for bacteria. Traces of blood were detected by urine stick test for haemoglobin volumes > 0.0015 microliters. RESULTS: Bacterial contamination was found in 32.8% of the total 1219 syringes and needles; 67% was caused by improper handling of the equipment after sterilization. Blood was detected in 12.5% of the samples. In the following three sampling strata, both contamination criteria were positive either on the syringe or the needle: wards/outpatient departments (OPD), 1.39%; laboratories, 7.45%; expanded programme on immunization (EPI), < 0.1%. We calculated that from 1.1 million patients injected in wards/OPD in any 1 year, fewer than 13 become infected, in laboratories fewer than 12 (160,000 blood-taking procedures), and less than one child in the EPI (850,000 vaccinations). CONCLUSION: With an established AIDS intervention programme supporting the health system, less than 0.4% of the total annual incidence of 4500-8500 is attributable to medical injections in the Mbeya Region.

High proportion of unrelated HIV-1 intersubtype recombinants in the Mbeya region of southwest Tanzania.

BACKGROUND: In Mbeya, a rural region of southwest Tanzania, HIV-1 subtypes A, C and D have been co-circulating since the early 1990s. OBJECTIVE: To define to what extent the co-existence of subtypes has led to recombinant HIV-1 strains and whether there is evidence for epidemic spread of any circulating recombinant form. METHODS: Nine HIV-1-seropositive young adults from Mbeya Town with no evident high-risk behaviour contributed peripheral blood mononuclear cells for this study. Nine virtually full-length-genome-sequences were amplified from this DNA and phylogenetically analysed. RESULTS: Out of the nine samples, two were subtype A (22%), two were subtype C (22%) and five were recombinants (56%): four A/C recombinants and one C/D recombinant. None of the recombinants were related to each other; all of them had different mosaic structures. Most of the genome in the recombinants was subtype C. CONCLUSION: A high proportion of unrelated intersubtype recombinants, none of them apparently spreading in the population, may be present in southwest Tanzania.

Reductions in risk behaviour provide the most consistent explanation for declining HIV-1 prevalence in Uganda.

OBJECTIVE: To monitor the HIV-1 epidemic in Western Uganda and the possible impact of interventions. DESIGN: Results from sentinel surveillance of HIV-1 seroprevalence were compared with cross-sectional serosurvey data and model simulations. METHODS: Age-specific trends in HIV-1 prevalence between 1991 and 1997 amongst antenatal clinic (ANC) attenders in the town of Fort Portal, where a comprehensive AIDS control programme has been implemented since 1991, were analysed. Results were compared with outputs from a mathematical model simulating the HIV-1 epidemic in Uganda. Two scenarios were modelled: one without and one with behaviour change. Sentinel surveillance data were compared with data from a population-based HIV-1 serosurvey at the study site, which was carried out in early 1995. RESULTS: Data from 3271 ANC attenders identified greater education and being single as risk factors for HIV-1 infection. A significant decrease of risk for women with secondary school education over time was observed, whereas the risk for illiterate women remained high. Among women aged 15-19 years (n = 1045) education and marital status-adjusted HIV-1 prevalence declined steadily from 32.2% in 1991 to 10.3% in 1997. For 20-24-year-old women (n = 1010) HIV-1 prevalence increased until 1993 from 19.9% to 31.7% and decreased thereafter (21.7% in 1997). These trends closely follow the prediction of the model simulation assuming behaviour change, and for 1995-1997, confidence intervals of the HIV-1 prevalence estimate exclude the model output for an uninfluenced epidemic. No clear trends of HIV-1 prevalence were found in older women (n = 1216) and comparisons with the model were ambiguous. Sentinel surveillance data at the time of the population survey closely reflected results for the female general population sample for the two younger age-groups (15-19 and 20-24 years). In contrast, pregnant women aged 25-29 years showed significantly lower rates than the population sample (20.8% versus 45.1%). CONCLUSION: HIV-1 prevalence amongst ANC attenders aged 15-24 years can be used to monitor the HIV-1 epidemic in the given setting. Declining trends of HIV-1 prevalence in women aged 15-19 and 20-24 years most likely correspond to a reduced HIV-1 incidence attributable to changes in behaviour. Our data also show that sentinel surveillance data need to be age-stratified to give useful information.

Diagnostic significance of blood eosinophilia in returning travelers.

This study was conducted to investigate the predictive value of blood eosinophilia (total white blood cell count with > or =8% eosinophils) for the diagnosis of travel-related infections in 14,298 patients who returned from developing countries. The data show that blood eosinophilia in travelers returning from developing countries has only limited predictive value for the presence of travel-related infections. However, the likelihood of the presence of helminth infections increases considerably with the extent of eosinophilia.

HIV type 1 V3 serotyping of Tanzanian samples: probable reasons for mismatching with genetic subtyping.

HIV-1 V3 serotyping is used to classify immunodeficiency viruses on the basis of antibody binding to V3 peptides derived from env genetic subtypes. Although it shows a reasonable overlap, it has been reported to be distinct from viral genetic subtypes. The aim of this study is to determine the feasibility of HIV-1 serotyping to predict genetic subtypes in an East African setting, where multiple HIV-1 subtypes have coexisted for many years. HIV-1 genetic subtypes of 86 AIDS patients in Mbeya Town, southwest Tanzania, were determined, using env nucleic acid sequencing as the basis for comparison. Those data were compared with V3 serotyping results obtained by four different methodologies. Four HIV-1 genetic subtypes were identified, including A (25, 29%), C (47, 55%), D (13, 15%), and G (1, 1%). The sensitivity and specificity of those serotyping assays varied considerably: sensitivity for genetic subtype A (40-48%), C (52-96%), and D (9-31%); and specificity for genetic subtype A (77-95%), C (46-63%), and D (97-100%). We further tried to identify reasons for the discrepancies between serotyping results and genetic subtypes. By means of logistic regression analysis three amino acid residues within the V3 loop (positions 12, 13, and 19; V, H, and A for serotype A, I, R, and T for serotype C) were found to be most important for antibody binding; a deviation from the subtype-specific amino acids was highly related to mismatched results. In addition, we have shown that phenetic analysis of V3 amino acid sequence data could be used to predict the majority of V3 serotypes (93-94%). Our data demonstrated that for the majority of specimens HIV-1 V3 serotyping results closely match the subtype of the analyzed sample as revealed by the V3 loop amino acid sequence. However, our data demonstrate that HIV-1 serotyping is not sufficiently accurate to predict genetic subtypes in Tanzania, where subtypes A, C, D, and G are circulating. This was due to highly similar amino acid sequences throughout the prevalent genetic subtypes, which caused the inability of HIV-1 V3 serotyping to differentiate subtype A from C as well as D from C. Instead, the serotyping results reflect the frequency distribution of V3 serotypes. To investigate HIV-1 genetic subtypes in population-based studies in this African setting additional or modified algorithms are needed.

PIP: HIV-1 V3 serotyping is used to classify immunodeficiency viruses on the basis of antibody binding to V3 peptides derived from env genetic subtypes. Findings are reported from a study conducted to determine whether HIV-1 serotyping could be effectively used to predict genetic subtypes in an East African setting, where multiple HIV-1 subtypes have coexisted for many years. The HIV-1 genetic subtypes of 86 people with AIDS in Mbeya Town, southwest Tanzania, were determined, using env nucleic acid sequencing as the basis for comparison. Those data were then compared with V3 serotyping results obtained by analysis with tests manufactured by Behring and the Pettenkofer Institute, tests conducted by St. Mary's Hospital Medical School, tests conducted by Georg-Speyer-Haus, and tests conducted by Universite Francois Rabelais. The following HIV-1 genetic subtypes were identified: 25 cases of A (29%), 47 of C (55%), 13 of D (15%), and 1 of G (1%). The sensitivity and specificity of the serotyping assays varied considerably. These data indicate that HIV-1 serotyping is not accurate enough to predict genetic subtypes in Tanzania. This conclusion was reached based upon the highly similar amino acid sequences throughout the prevalent genetic subtypes, which caused the inability of HIV-1 V3 serotyping to differentiate subtype A from C as well as D from C. The serotyping results instead reflect the frequency distribution of V3 serotypes.

Long-term efficacy of primaquine in the treatment of vivax malaria in nonimmune travelers.

Fifty-six travelers presenting with vivax malaria to a German travel clinic were followed regularly for at least 18 months between 1984 and 1992 to investigate the long-term efficacy of primaquine in nonimmune patients without reinfection. All received a standard treatment of 15 mg of primaquine a day for 14 days following an initial total dose of 1,500 mg of chloroquine (base) given over a 48-hr period. None of the patients visited countries endemic for malaria during the period of observation. In seven patients (12.5%), relapses were confirmed microscopically by detection of malaria parasites in blood films. The frequency of relapses varied between one and four per patient and these occurred between 60 and 252 days after treatment. Four of these seven patients had acquired infection in Papua New Guinea or eastern Indonesia, while only five (10.2%) of the remaining 49 patients without relapses had traveled to these areas prior to referral (P < 0.01).

Plasmodium falciparum resistance to sulfadoxine/pyrimethamine in Uganda: correlation with polymorphisms in the dihydrofolate reductase and dihydropteroate synthetase genes.

The efficacy of sulfadoxine/pyrimethamine (S/P) in treatment of uncomplicated falciparum malaria in Africa is increasingly compromised by development of resistance. The occurrence of active site mutations in the Plasmodium falciparum gene sequences coding for dihydrofolate reductase (DHFR) and dihydropteroate synthetase (DHPS) is known to confer resistance to pyrimethamine and sulfadoxine. This study investigated the occurrence of these mutations in infected blood samples taken from Ugandan children before treatment with S/P and their relationship to parasite breakthrough by day 7. The results confirm the occurrence of mutations in DHFR and DHPS that were significantly selected under S/P pressure at day 7: a combination of alleles 51-isoleucine and 108-asparagine in DHFR, and 436-serine, 437-alanine, 540-lysine and 581-alanine in DHPS, appears to play a major role in the development of in vivo resistance in P. falciparum strains against S/P. Therefore, earlier results derived from isolates from hyperendemic areas in Tanzania were confirmed by this investigation.

Geographic differences in the sensitivity of a polymerase chain reaction for the detection of Plasmodium falciparum infection.

The amplification of target DNA by highly specific probes using the polymerase chain reaction (PCR) provides a highly sensitive and specific method for the detection of malaria infection. The use the of PCR in settings with varying endemicity within one survey area has not been investigated intensively. Therefore, a cross-sectional study was conducted in the districts of Kabarole and Bundibugyo in western Uganda using material from three villages with different epidemiologic situations regarding malaria and DNA primers for a PCR that had shown satisfactory sensitivity and specificity in previous trials. The sensitivity of the PCR varied significantly (P < 0.001) in the three survey villages (between 63.2% and 83.9% for the primer pair K1-14-1 and between 37.9% and 69.9% for the primer pair MSP-1) and was highly linked to geographic differences and social exchanges of the inhabitants with other areas of the district. According to the results of this investigation, it is advisable not to use a single primer pair in epidemiologic field studies for the detection of falciparum malaria. The use of combined primer pairs and the frequent confirmation of the results by microscopy are recommended.

Diagnostic value of molecular markers in chloroquine-resistant falciparum malaria in Southern Mauritania.

Despite its diminishing efficacy because of increased resistance, chloroquine remains the primary antimalarial agent in many endemic areas. Evidence is mounting that point mutations on the Pfcrt and possibly the Pfmdr1 genes are conferring plasmodial resistance to chloroquine. In 1998, atypically strong rainfalls led to an increased activity of falciparum malaria in Mauritania that affected non-endemic regions bordering the Saharan desert. An in vivo study on chloroqine resistance was combined with studies for molecular markers of drug resistance. Detection of Pfmdr1-76-tyrosine showed an increased odds ratio (2.91) for resistance (P = 0.0195). However, by use of this codon alone, sensitivity for detection of resistance was 60.6%, and specificity was 65.3%. In comparison, detection of the K76T mutation at Pfcrt showed a very high sensitivity (100%) while specificity remained relatively low (65.4%). For the combination of mutations on both genes, the odds ratio for detection of resistance increased to 5.31 (P = 0.0005). Here, sensitivity was again decreased to 60.6% while specificity increased to 76.9%. The results of this study suggest that detection of Pfcrt T76 can be applied for predicting chloroquine resistance in epidemiologic settings with sufficiently high sensitivity to make it an attractive alternative to time- and labor-consuming in vivo trials. Additional testing for Pfmdr Y76 provides increased specificity to this approach.

Plasmodium falciparum: selection of serine 108 of dihydrofolate reductase during treatment of uncomplicated malaria with co-trimoxazole in Ugandan children.

In vivo testing for resistance of Plasmodium falciparum to co-trimoxazole (trimethoprim/sulfamethoxazole) was performed in Uganda in 41 children with uncomplicated malaria, and blood samples were screened before and after treatment for polymorphisms in the antifolate target genes for dihydrofolate reductase (DHFR) and dihydropteroate synthetase (DHPS). Selection towards a specific genotype at some codons of the DHFR and DHPS genes was observed in samples collected after exposure to co-trimoxazole drug pressure. The alleles 51-isoleucine, 59-arginine, and 108-serine of DHFR were significantly associated with clinical resistance, as was allele 581-alanine of DHPS. Resistance against antifolate combinations probably requires resistance-related polymorphisms in both the DHFR and the DHPS genes. In addition, it appears that the trimethoprim-resistant DHFR genotype differs from that for pyrimethamine at residue 108.

Resistance in vivo of Plasmodium falciparum to co-trimoxazole in western Uganda.

In the context of the 'integrated management of childhood illnesses' (IMCI) programme the World Health Organization recommends treating children in malarious areas presenting with fever and respiratory symptoms with co-trimoxazole. In order to verify its effectiveness in uncomplicated Plasmodium falciparum malaria we carried out a study in vivo in western Uganda: 180 children under 5 years old were enrolled and treated with 40/8 mg/kg/d co-trimoxazole over 5 d, and 159 could be followed on days 3, 7 and 14. Effectiveness of treatment was found to be significantly different in various parts of the study area. In Bundibugyo District, bordering République Democratique du Congo (Zaire), 59.1% (39/66) of children were clinically cured after 14 d and 56.1% were parasitologically cured. In the east of Kabarole District (43 children), the figures were 76.7% and 65.1%, respectively. In western Kabarole (50 children) the rates were 96.0% and 90.0%, respectively. We conclude that, in view of the high level of clinical failures in parts of the study area, co-trimoxazole should not be used in the IMCI programme for combined treatment of malaria and pneumonia in the region. Assessment of therapeutic effectiveness of antimalarial drugs needs to consider the microepidemiology of resistance.

Application of the ParaSight-F dipstick test for malaria diagnosis in a district control program.

A rapid test for the diagnosis of Plasmodium falciparum infections based on the detection of histidine-rich-protein II, the ParaSight-F test, was evaluated after introduction in a district malaria control program in Uganda. Suspected treatment failures, pregnant women and infants with clinical malaria and general fever cases were tested at health facilities in malaria hypo-, meso- and holoendemic areas. A total of 1326 tests were carried out by health unit staff, cross read by experienced laboratory staff and results compared with thick film microscopy as the standard. Rater agreement in reading the dipstick result between health unit staff and laboratory staff was high, kappa index 0.94 (0.88-0.99). Sensitivity was 99.6% (99.0-100) for parasite densities above 500/microl, 98.6% (97.7-99.6) for densities above 50/microl and 22.2% (8.6-42.3) for densities below 10/microl. With the applied testing strategies no differences were found between endemicity levels or patient categories. Specificity was 86.2% (83.3-88.8) overall, but significantly higher in general fever cases (92.7%) compared to the other patient groups (84.3%, P=0.009). At the given prevalences positive predictive values (ppv) were above 80% and negative predictive values (npv) above 90% in all cases except in pregnant women (ppv: 77.8%). We conclude that in certain situations this test is an alternative to microscopy to improve diagnostic facilities for case management in malaria control programs in endemic African countries.