1.Cryptosporidiosis among children with diarrhoea in three Asian countries:A review
Latif Baha ; Rossle Fariza Nurul
Asian Pacific Journal of Tropical Biomedicine 2015;(11):841-844
This review focuses on studies concerning cryptosporidiosis in three Asian countries. Cryptosporidium spp. infection was investigated in children<12 years old afflicted with diarrhoea and admitted to the paediatric hospitals in Iraq, Jordan and Malaysia. Most of the patients complained of abdominal pain, watery diarrhoea and mild-to-severe dehydration. Stool samples were collected from children and five methods were used to detect oocysts of Cryptosporidium spp. including:direct wet mount, Sheather’s sugar flotation, formalin-ether sedimentation, modified Ziehl-Neelsen and direct fluorescent antibody (DFA). The infection rate was 8.56, 37.3 and 4.6 in Iraq, Jordan and Malaysia respectively. A combination of formalin ether sedimentation and acid fast stain was used to detect Cryptosporidium oocysts in Iraq. The DFA test showed the highest sensitivity for samples of children in Jordan. In Malaysia, direct wet mount, formalin-ether sedimentation, modified Ziehl-Neelsen and DFA gave the same results (4.62%) while Sheather’s sugar flotation was 3.85%. Source of drinking water appeared to be an important risk factor in transmission of infection. In Jordan, the high rate of infection was recorded in rainy season (January–May).
2.Cryptosporidiosis as threatening health problem:A review
Rossle Fariza Nurul ; Latif Baha
Asian Pacific Journal of Tropical Biomedicine 2013;(11):916-924
The protozoa under the genus Cryptosporidium is a zoonotic apicomplexan obligate intracellular parasite. Cryptosporidiosis, the term used to designate infection caused by Cryptosporidium sp., is considered as one of the most common food and waterborne diseases with worldwide spread, acting as a common cause of diarrhoea in animals and man. In immunocompetent individuals, Cryptosporidium typically induces self-limiting diarrhoea, which may resolve on its own after 2-3 d. However, cryptosporidiosis may turn life-threatening and subsequently lead to death in small children, the elderly and immunocompromised person, especially in AIDS patient. The diagnosis for Cryptosporidium infection is usually carried out through examination of stool for the presence of oocysts which measured 4-6 μm with spherical appearance. Morphometric identification is often difficult because of the diminutive size and obscure internal structure of the protozoa. Often, the identification of Cryptosporidium is realised through the combination of methods incorporating data from morphometrics, molecular techniques, and host specificity. However, limitations to some of these techniques still exist whether because of cost, duration, expertise, or reliability. Drugs combination is implemented in treatment of cryptosporidiosis. The efficiency of paromomycin, an aminocyclitol antibiotic isolated from Streptomyces, can be effective when combined use with protease inhibitors or recombinant IL-12. Since there is no drug that achieves the complete removal of Cryptosporidium from the host, supportive therapy was preferred in both human and domestic animals.
3.Isolation of Acanthamoeba spp. from Aquatic Environment
Nurul Fariza Rossle ; Mohamed Kamel Abd Ghani ; Anisah Nordin ; Yusof Suboh ; Noraina Abd Rahim
Malaysian Journal of Health Sciences 2010;8(2):15-19
This study was carried out to isolate Acanthamoeba spp. from various aquatic environments in Peninsular Malaysia. A
total of 160 samples were collected with 140 samples using direct swab method and 20 samples using water collection
method with 500 ml sterile Schott bottle. The swab samples were taken from water tap (50), sink (50), and swimming
pool (40) while the water samples were from seawater. Swab samples were inoculated directly onto non-nutrient agar
(NNA) seeded with heat-killed Escherichia coli using aseptic technique. Water samples were first filtered through a 0.45μm pore size membrane before the membrane was transferred aseptically onto NNA plate seeded with heat-killed E. coli.
All plates were incubated at 30°C and examined daily for the presence of Acanthamoeba spp. up to 14 days after
incubation before being declared negative. Overall, 20% samples were positive for the presence of Acanthamoeba.
Positive isolation of Acanthamoeba spp. from sink and swimming pool were 20% and 30%, respectively. All three
groups of Acanthamoeba genus in cyst form could be found from the collected samples.
4.Ability of Acanthamoeba Cyst to Excyst at Different Temperatures
Nurul Fariza Rossle ; Anisah Nordin ; Yusof Suboh ; Noraina Ab Rahim ; Mohamed Kamal Abd Ghani
Malaysian Journal of Health Sciences 2011;9(1):41-43
This study was carried out to observe thermotolerance ability of Acanthamoeba spp. A total of 32 Acanthamoeba spp. isolates obtained from water taps, sinks, swimming pools and sea water were used. Trophozoites of Acanthamoeba spp. were inoculated onto non-nutrient agar (NNA) seeded with heat-killed Escherichia coli using aseptic technique and incubated for 14 days at 30°C to obtain the cyst. The cysts were subcultured onto new agar plates for thermotolerance test at 37°C and 42°C. The plates were observed until 96 hours after incubation for excystation of Acanthamoeba before being declared negative. Overall, 81.25% of samples were able to excyst at 37°C while 37.5% were able to excyst at
42°C. Thermotolerant Acanthamoeba is associated with high pathogenicity potential.
5. Cryptosporidiosis among children with diarrhoea in three Asian countries: A review
Baha LATIF ; Nurul Fariza ROSSLE
Asian Pacific Journal of Tropical Biomedicine 2015;5(11):885-888
This review focuses on studies concerning cryptosporidiosis in three Asian countries. Cryptosporidium spp. infection was investigated in children < 12 years old afflicted with diarrhoea and admitted to the paediatric hospitals in Iraq, Jordan and Malaysia. Most of the patients complained of abdominal pain, watery diarrhoea and mild-to-severe dehydration. Stool samples were collected from children and five methods were used to detect oocysts of Cryptosporidium spp. including: direct wet mount, Sheather's sugar flotation, formalin-ether sedimentation, modified Ziehl-Neelsen and direct fluorescent antibody (DFA). The infection rate was 8.56, 37.3 and 4.6 in Iraq, Jordan and Malaysia, respectively. A combination of formalin ether sedimentation and acid fast stain was used to detect Cryptosporidium oocysts in Iraq. The DFA test showed the highest sensitivity for samples of children in Jordan. In Malaysia, direct wet mount, formalin-ether sedimentation, modified Ziehl-Neelsen and DFA gave the same results (4.62%) while Sheather's sugar flotation was 3.85%. Source of drinking water appeared to be an important risk factor in transmission of infection. In Jordan, the high rate of infection was recorded in rainy season (January-May).