Measles Surveillance

 Suspected measles case-based surveillance, South Africa, 2012
 
Reporting period 01/01/2012 to 30/09/2012
 
The case-based measles surveillance programme with laboratory support started in 1998 as part of the National Department of Health’s measles elimination strategy. The National Institute for Communicable Diseases (NICD) of the National Health Laboratory Service (NHLS) is accredited by the World Health Organization (WHO) to perform measles and rubella IgM testing for the national case-based surveillance. Blood and urine or throat swab specimens from suspected measles cases (patients with fever >38°C and rash, and at least one of: cough, coryza or conjunctivitis) nationally are submitted to the NICD_NHLS for laboratory confirmation.
 
The numbers presented here represent specimens received by the NICD_NHLS and may differ from those presented by the National Department of Health as they may receive information on cases where no specimens were taken.
 
Comment 
 This year to date (30 September 2012), the NICD tested 4227 specimens from 4186 suspected measles cases, 100 of which were collected in 2011. Of those collected in 2012 (n=4086), 31% (1288/4086) were rubella IgM positive and 0.7% (28/4086) measles IgM positive (11 of which were vaccine-related). In addition three equivocal measles IgM were confirmed by PCR.
 
Rubella: Age was reported in 98% (1264/1288) of rubella IgM positive cases. Age ranged from <1 month to 87 years with a median of 6 years. Children aged <12 years accounted for 88% (1129/1288) of the cases.  Where age and sex were recorded (n=1231), females accounted for 50% (614/1231) of the cases and 6% (69/1231) were among women of child-bearing age 12-49 years. Rubella IgM positive cases were reported from all nine provinces with KwaZulu-Natal (417/1288, 32%), Eastern Cape (256/1288, 20%) and Western Cape (162/1288, 13%) provinces accounting for the highest proportion of the total cases (Table 1).
 
Measles: Laboratory-confirmed measles cases were reported from six provinces (Table 1). Seven of the cases were aged <5 years (five of which were under 1 year) while nine were ≥5 years old.



 
 
Table 1: Number of laboratory-confirmed cases by province
  

Province Measles IgM positive Rubella IgM positive
Eastern Cape 0 256
Free State 1 27
Gauteng 6 131
KwaZulu-Natal 6 417
Limpopo 1 30
Mpumalanga 0 95
Northern Cape 0 112
North West 1 58
Western Cape 1 162
South Africa 16 1288


 

 
 
Figure 1: Number of laboratory-confirmed measles cases and detection rate by week specimens were collected,South Africa,January-September 2012



Figure 2: Number fo rubella IgM positive samples and detection rate by week specimens were collected,South Africa,January - September 2012


Source: Centre for Vaccines and Immunology,NICD
This report only includes suspected measles cases tested at the NICD. Data presented are provisional, as reported to date,positives are analysed by date of collection. Data may be freely reproduced provided due acknowledgement is given to NICD