To understand the transmission of Cryptosporidium infection in children, fecal specimens from 62 Kuwaiti children with gastrointestinal symptoms found to be positive by microscopy were genotyped and subtyped with a small subunit rRNA-based PCR-restriction fragment length polymorphism analysis and a 60-kDa glycoprotein-based DNA sequencing tool. The median age of infected children was 4.5 years, and 77% of infections occurred during the cool season of November to April. Fifty-eight of the children (94%) had Cryptosporidium parvum, three (5%) had Cryptosporidium hominis, and one (1%) had both C. parvum and C. hominis. Altogether, 13 subtypes of C. parvum (belonging to four subtype allele families) and C. hominis (belonging to three subtype allele families) were observed, with 92% of specimens belonging to the common allele family IIa and the unusual allele family IId. Thus, the transmission of cryptosporidiosis in Kuwaiti children differed significantly from other tropical countries.Cryptosporidiosis is a significant cause of diarrheal diseases in both developing and industrialized nations. Recent molecular epidemiologic studies of cryptosporidiosis have helped researchers to better understand the transmission of cryptosporidiosis in humans and the public health significance of Cryptosporidium spp. in animals and the environment. Using genotyping tools, five species of Cryptosporidium (C. hominis, C. parvum, C. meleagridis, C. felis, and C. canis) have been shown to be responsible for most human infections. Of these five species, C. hominis and C. parvum are the two most common species (34). Because these five human pathogenic Cryptosporidium species have different spectrums of host specificity, the characterization of Cryptosporidium at the species level is useful in investigating infection and contamination sources. Recently, a number of subtyping tools have been developed and used to characterize the population structure and transmission dynamics of C. parvum and C. hominis (2, 8, 17, 18, 24-26, 29, 30).Although cryptosporidiosis is prevalent in tropical regions, limited studies have been conducted to characterize Cryptosporidium spp. from humans at the molecular level. Several studies have examined the transmission of human cryptosporidiosis in South Africa, Malawi, Kenya, Uganda, Peru, and Thailand, all of which have shown a predominance of C. hominis in humans, indicating anthroponotic transmission plays a major role in the epidemiology of cryptosporidiosis in most tropical countries (7,17,25,(31)(32)(33). Only two of the studies subtyped small numbers of Cryptosporidium spp. (17,25). In the present study, 62 Cryptosporidium-positive specimens were collected from children in Kuwait City between 1997 and 2004 and examined by a small subunit (SSU) rRNA-based PCR-restriction fragment length polymorphism (PCR-RFLP) analysis and a 60-kDa glycoprotein (GP60)-based PCR sequencing tool (2, 33). Results of the study have shown a predominance in children of C. parvum, which traditionally is associated with farm animal...

Conventional light microscopy has been the established method for malaria diagnosis. However, recently several nonmicroscopic rapid diagnostic tests have been developed for situations in which reliable microscopy may not be available. This study was conducted to evaluate the diagnostic performance of a recently introduced ICT Malaria Pf/Pv test. This assay detects Plasmodium falciparum histidine-rich protein 2 antigen (PfHRP-2) for P. falciparum diagnosis and pan-malarial antigen for P. vivax diagnosis. In this study we compared the performance of ICT Malaria Pf/Pv with microscopy of Giemsa-stained blood films and with an OptiMAL test that detects Plasmodium lactate dehydrogenase (pLDH) antigen. A total of 750 clinically suspected malaria patients were examined at local health centers in Kuwait. Both the antigen tests had a high degree of specificity (>98%) for detection of malaria infection. However, they were less sensitive than microscopy. Compared with microscopy the ICT Malaria PF/pf test failed to detect malaria infection in 93 (34%) of 271 malaria patients (11% of patients with P. falciparum and 37% of patients with P. vivax) and the OptiMAL test failed to detect malaria infection in 41 (15%) of 271 malaria patients (7% of patients with P. falciparum and 13% of patients with P. vivax). The sensitivities of the ICT Malaria Pf/Pv and OptiMAL tests for detection of P. falciparum infection were 81 and 87%, and those for detecting P. vivax were 58 to 79%, respectively. The sensitivity of the ICT Malaria Pf/Pv and OptiMAL tests decreased significantly to 23 and 44%, respectively, at parasite densities of <500/l. Both of the tests also produced a number of false-positive results. Overall, the performance of the OptiMAL test was better than that of the ICT Malaria Pf/Pv test. However, our results raise particular concern over the sensitivity of the ICT Malaria Pf/Pv test for detection of P. vivax infection. Further developments appear necessary to improve the performance of the ICT Malaria Pf/Pv test.

To determine the association of clinical characteristics with Cryptosporidium types and subtypes, faecal specimens from 2548 children with diarrhoea were screened by microscopy for Cryptosporidium spp., and positive specimens were genotyped and subtyped by PCR-RFLP. A total of 87 of the 2548 children (3.4 %) had cryptosporidial diarrhoea by microscopy and the majority (41.4 %) of the infected children were in the 4-8-year-old age group. Molecular characterization of the 83 children studied further (4 had mixed infections and were not subtyped) showed that Cryptosporidium parvum was the most commonly identified species (73.5 %) and consisted of three subtypes: IIa and IId were the most common (80.3 %), followed by IIc. Twentytwo (26.5 %) of the children had Cryptosporidium hominis and showed three subtypes: Id was the most common (54.5 %), followed by Ia (36.4 %) and Ie. Associated clinical manifestations varied between C. parvum and C. hominis. Diarrhoea associated with subtype Id, the most commonly identified C. hominis subtype, was more severe than that associated with other subtypes. In conclusion, this study confirmed a very different Cryptosporidium genotype and subtype distribution compared with other tropical countries among Kuwaiti children with diarrhoea, with a predominance of C. parvum IIa and IId. In addition, subtype Id of C. hominis was associated with more diverse and severe clinical manifestations in infected children, suggesting that parasite genetics may play an important role in the clinical manifestations of human cryptosporidiosis.

Acute Toxoplasma gondii infection in early pregnancy carries the risk of transmitting the infection to the fetus with serious sequelae. However, serological testing for IgG/IgM anti-Toxoplasma antibodies may fail to differentiate between a recent and past infection. Two hundred and twentyfour Kuwaiti women in their first trimester were screened for IgG/IgM antibodies by the Vitek Immuno Diagnostic Assay System (VIDAS) and VIDAS IgG-avidity tests. On serological screening, 119 (53.1 %) women were positive for IgG antibodies and 31 (13.8 %) for IgM antibodies. Nine of the IgM-positive and 7 IgM-negative women had low-avidity antibodies. However, the IgG-avidity test detected low-avidity antibodies only in 9 (29 %) of the 31 IgMpositive women, suggesting a recent infection; 19 (61.3 %) women had high-avidity antibodies, indicating that the infection was acquired in the distant past. Based on IgM serology alone, at least 31 IgM-positive women may have been wrongly labelled as having acute Toxoplasma infection thus warranting appropriate therapeutic intervention. All the 19 IgM-positive women with highavidity antibodies were confirmed negative for Toxoplasma DNA on PCR analysis. Compared with PCR analysis, the VIDAS avidity test was a helpful tool for the diagnosis of recent Toxoplasma infection in IgM-negative women with low-avidity antibodies and IgM-positive women with highavidity antibodies; the specificity was .85 -100 %. It is concluded that the VIDAS avidity test when used in combination with VIDAS IgG/IgM tests is a valuable assay for the exclusion of ongoing or recently acquired T. gondii infection in pregnant women in their first trimester and that it decreases significantly the necessity for follow-up testing and unnecessary therapeutic intervention.

Abstract. The OptiMAL test detects both Plasmodium falciparum and P. vivax malaria infections. In this study, we evaluated the performance of the OptiMAL test at the Basic Health Units (BHUs) and the District Health Quarter (DHQ) Center in rural villages of Punjab, Pakistan that provide minimal health services. Two sets of blood specimens obtained from 930 suspected malaria patients attending these BHUs were tested at BHUs and the DHQ Center by microscopy and the OptiMAL test. At the BHUs, 231 (25%) of the patients were positive by microscopy and 278 (30%) patients tested positive by the OptiMAL test. At the DHQ Center, microscopic analysis of a second set of specimens from the same patients confirmed the malaria infection in 386 (42%) patients and the OptiMAL test result was positive in 300 (32%) patients. To determine the performance of OptiMAL test at the BHUs and the DHQ Center, all data were compared with microscopy results obtained at the DHQ Center. The OptiMAL test results for P. falciparum at the BHUs were comparable to those of the OptiMAL test at the DHQ Center. However, the sensitivity, positive predictive value (PPV), and negative predictive value (NPV) of the OptiMAL test were considerably lower for P. vivax infections than for P. falciparum infections, irrespective of whether the test was performed at the BHUs or at the DHQ Center (P. falciparum: sensitivity ‫ס‬ 78-85%, PPV ‫ס‬ 89-97%, NPV ‫ס‬ 96-98%; P. vivax: sensitivity ‫ס‬ 61-76%, PPV ‫ס‬ 88-95%, NPV ‫ס‬ 90-93%). The OptiMAL test also detected a number of false-positive and false-negative results at both the BHUs and the DHQ Center. The false-positive results ranged from 1% to 2%; however, the number of false-negative results was much higher (BHUs: P. falciparum ‫ס‬ 22%, P. vivax ‫ס‬ 39%; DHQ Center: P. falciparum ‫ס‬ 15%, P. vivax ‫ס‬ 24%). In conclusion, these results, when combined with other advantages of the OptiMAL test, suggest that this test can be used by relatively inexperienced persons to diagnose malaria infection in rural areas where facilities for microscopy are not available.