Absence of lymphatic filariasis infection among secondary-school children in Oman.

The endemicity status of lymphatic filariasis in Oman is uncertain, with only sporadic cases reported, mostly imported. Immunochromatographic card test surveys were carried out to assess the presence of circulating Wuchereria bancrofti antigenaemia as a marker for active infection in children from suspected high-risk areas of Oman (South Batinah and Dhofar). Lot quality assurance sampling surveys were carried out on a minimum of 250 secondary-school children aged 17-18 years in each of 8 districts from February 2004 to March 2004. All tested students were negative for circulating W. bancrofti antigen. Based on these findings as well as previous data, Oman may possibly be classified as a nonendemic country, with no evidence of indigenous lymphatic filariasis transmission.

Absence of lymphatic filariasis infection among secondary-school children in Oman

The endemicity status of lymphatic filariasis in Oman is uncertain, with only sporadic cases reported, mostly imported. Immunochromatographic card test surveys were carried out to assess the presence of circulating Wuchereria bancrofti antigenaemia as a marker for active infection in children from suspected high-risk areas of Oman [South Batinah and Dhofar]. Lot quality assurance sampling surveys were carried out on a minimum of 250 secondary-school children aged 17-18 years in each of 8 districts from February 2004 to March 2004. All tested students were negative for circulating W. bancrofti antigen. Based on these findings as well as previous data, Oman may possibly be classified as a nonendemic country, with no evidence of indigenous lymphatic filariasis transmission

Measles epidemiology and its implications for a vaccination programme in Oman.

To describe the epidemiology of measles in Oman and the implications for a vaccination programme, we conducted a retrospective record-based study from 1 January 2000 to 31 December 2003 using data from the national epidemiological surveillance system. All cases notified as suspected measles during the study period were included. Of the 185 notified cases, 19.4% were confirmed measles positive. Blood samples for measles IgM were collected in 97.3% of cases. The mean age of measles cases was 8.0 (SD 10.7) years. The estimated overall incidence rate of measles for the study period was 0.53 per 100,000 person-years. Regression analysis indicated measles was significantly commoner among non-Omanis and children who had not been vaccinated.

Measles epidemiology and its implications for a vaccination programme in Oman

To describe the epidemiology of measles in Oman and the implications for a vaccination programme, we conducted a retrospective record-based study from 1 January 2000 to 31 December 2003 using data from the national epidemiological surveillance system. All cases notified as suspected measles during the study period were included. Of the 185 notified cases, 19.4% were confirmed measles positive. Blood samples for measles IgM were collected in 97.3% of cases. The mean age of measles cases was 8.0 [SD 10.7] years. The estimated overall incidence rate of measles for the study period was 0.53 per 100 000 person-years. Regression analysis indicated measles was significantly commoner among non-Omanis and children who had not been vaccinated

Poliomyelitis in Oman. I. The last outbreak?

Since 1988, the Sultanate of Oman has experienced three outbreaks of paralytic poliomyelitis. The last outbreak occurred in December 1993 and involved two children aged 10 months and 4 1/2 years. The children had received five and four doses, respectively, of trivalent oral polio vaccine (OPV) and lived in the same village. Serum neutralizing antibody tests suggested that paralytic polio in these children was due to poor antibody response to OPV. Wild poliovirus type 1 was isolated from both patients, as well as from seven of ten close contacts of the older child, and one of eight contacts of the younger child. All contacts had received three to six doses of OPV. Genomic sequence studies indicated that the virus isolates belonged to a genotypic group prevalent in southern and western Asia, but differed markedly from virus isolated during the 1988/89 outbreak, suggesting another importation of poliovirus. In response to the outbreak, supplementary immunization with OPV was given to children <6 years of age, initially in the affected district, and subsequently to children in the whole country. This study demonstrates that immunization with three to six doses of OPV did not prevent infection with wild poliovirus. In those children with sub-optimal response to OPV, infection resulted in paralytic poliomyelitis. The outbreak remained localized in one village, indicating that the outbreak control measures were effective.

Poliomyelitis in Oman. II. Toward eradication.

In the past decade, the Sultanate of Oman has experienced three outbreaks of paralytic poliomyelitis--a widespread polio type 1 epidemic in 1988/1989, four cases of polio type 3 in three different regions in 1991, and a localized type 1 outbreak in 1993. The lessons learnt from each of these epidemics have guided us to modify and improve our polio eradication activities. Currently, these activities include administration of five primary and three booster doses of trivalent oral polio vaccine, yearly national immunization campaigns (NIDs) since 1995 with coverage of >90%, localized immunization campaigns, acute flaccid paralysis (AFP) surveillance which involves reporting of all cases by facsimile to the Department of Surveillance within 24 h of detecting a case and weekly zero reporting from 22 sentinel sites, and virological testing of stool specimens of all AFP cases and their close contacts at the national, World Health Organization accredited laboratory. The cumulative success of these activities has resulted in Oman being free from polio for the past 6 years. However, the possibility of importation of wild poliovirus, particularly from southern and western Asia still exists.

Drug-susceptibility pattern of mycobacterium tuberculosis among pulmonary tuberculosis patients in riyadh, saudi arabia.

OBJECTIVE: To identify the pattern of drug-susceptibility of newly diagnosed pulmonary tuberculosis patients in Riyadh, we conducted a study on all Mycobacterium tuberculosis positive-culture patients admitted to Sahari Chest Hospital from January 1994 to April 1995. METHODS: Demographic data, antituberculous therapy and drug-susceptibility testing results of each patient were reviewed from patients' hospital records. The samples were cultured on Lowenstein-Jensen media and drug susceptibility was tested by Bactec 12B (Middlebrook 7H12) media against selected antituberculous drugs RESULTS: Drug susceptibility was performed on 362 (91%) of the sputum positive-cultures. The overall initial resistance rate (1 or more drugs) was 12.4%. Initial. resistance was more common with a single drug (9.4%), followed by two drugs (2.3%) and then three drugs (0.3%). Resistance to isoniazid was most common (10.4%), followed by streptomycin (2.7%), rifampicin (1.9%) and ethambutol (0.6%). Single isoniazid resistance was 60%, followed by two drugs: streptomycin and isoniazid (13.3%). CONCLUSION AND RECOMMENDATIONS: Resistance to multiple drugs is not yet a significant problem in Riyadh. A continuous monitoring of drug resistance is important for planning and assessing the national TB control program. Timely and complete reporting is essential to identify the problem as and when it begins.