17 February 2010
By Conrad Prabhu
International experts representing the World Health Organisation (WHO) and the Centres for Disease Control and Prevention (CDC) of the United States arrive next week on a week-long mission to learn from Oman's ongoing success in combating measles. The visit is seen as a testament to the world-class standards of the Sultanate's immunisation and surveillance programme targeting measles, a highly contagious viral disease that mostly affects children.
According to Health Ministry officials, the experts will review the Sultanate's anti-measles campaign as part of a wider study aimed at formulating criteria that can be employed in validating the efficacy of measles elimination programmes. "This forthcoming visit by representatives from the WHO and CDC is a tacit recognition of the superior standards of our measles vaccination and surveillance programme.
Oman enjoys a very low incidence of measles, primarily due to the high coverage achieved by our immunisation programme. This makes the Sultanate an ideal candidate for this kind of study," an official explained. The visit, which kicks off on Saturday, will include meetings with officials of the Department of Communicable Diseases Surveillance and Control.
The two-member team will discuss the measles situation in Oman, review laboratory procedures for measles diagnosis, and also assess the sensitivity of Oman's measles surveillance programme.
The WHO describes measles as a leading cause of vaccine-preventable childhood mortality. Global mortality rates have fallen in the wake of national vaccination campaigns, supported by international organisations like the WHO, Measles Initiative, CDC, and Unicef.
Globally, measles fell 60 per cent from an estimated 873,000 deaths in 1999 to 164,000 in 2008, the majority of them occurring within the South-East Asian region.
Although a relatively mild illness, its potential to cause serious harm among young children in developing countries has galvanised the WHO into making its elimination a new priority. While a majority of patients eventually recover from the disease, it can lead to encephalitis and brain damage in serious infections - an occurrence not uncommon in developing countries with poor immunisation programmes.
Any country claiming to having eliminated measles would necessarily mean that it has brought down the incidence level to the WHO stipulated benchmark of one case per million population. Validating this claim would require that a suitable tool be developed to assess the sensitivity of that country's surveillance progamme, particularly in light of the general perception that measles is a non-serious illness where sufferers make a recovery without any medical intervention.
The Ministry of Health launched its measles vaccination programme targeting infants in the early 1980s. A catch-up campaign, introduced in 1994, covered unvaccinated segments of the population of ages 15 months to 18 years. This campaign, combining vaccines for measles and rubella (MR), led to a high 90 per cent coverage.
In 1997, a vaccine for mumps was added to the measles-rubella vaccine combination leading to the 'MMR' vaccine that is today a key feature of the Ministry's Expanded Programme of Immunisation (EPI) covering all newborns and infants. The ministry also continues to routinely investigate all rash and fever syndromes for potential measles or rubella infection.
Despite the comprehensive immunisation coverage, Oman has not been entirely free from measles outbreaks - blamed primarily on importations or spillover influences from neighbouring countries. Outbreaks reported in recent years in Ibra, Buraimi, Dibba and Dhofar were quickly contained by health authorities.
© Oman Daily Observer 2010