Polio update: Tajikistan and central Asia

According to preliminary data received by WHO, almost 1.1 million children under the age of 6 received the first of 3 doses of monovalent oral polio vaccine (mOPV1) in Tajikistan’s countrywide poliomyelitis (polio) vaccination programme. The drive aims to contain a recent outbreak in which the infection of 56 children with wild poliovirus has been laboratory confirmed. The first round of the campaign ended on 8 May 2010; the second round will take place on 18–22 May and the third is planned for 1–5 June.

A WHO expert team has been in Tajikistan since 16 April, investigating the outbreak and providing technical support to the Government, in partnership with the United Nations Children’s Fund (UNICEF). The vaccination programme is supported by all members of the Global Polio Eradication Initiative, and several additional partners – funders, humanitarian agencies and nongovernmental organizations – are helping to contain the outbreak.

As of 9 May 2010, Tajikistan had reported 278 cases of acute flaccid paralysis (AFP). Of these, 56 have been laboratory confirmed as cases of wild poliovirus type 1, and 5 have been confirmed negative for poliovirus. So far, all AFP cases have occurred in south-western Tajikistan and the capital, Dushanbe. At present, there is no evidence of polio transmission to the Soghd region and Gorno-Badakhshan Autonomous Region of Tajikistan. The outbreak has affected 30 out of 68 administrative districts. Of the 56 confirmed wild poliovirus cases, 52 (93%) are in children under age 6, and 57% of the polio-stricken patients are male.

WHO, UNICEF and their international partners are assisting the Government of Tajikistan to vaccinate all children under 6, including those belonging to minority and refugee groups. WHO and UNICEF have begun to map populations living in hard-to-reach mountain areas or near the borders with Afghanistan and Uzbekistan. The Office of the United Nations High Commissioner for Refugees (UNHCR) is helping to identify these groups.

WHO has informed all countries in central Asia that it does not recommend restricting travel or trade, but focusing the public health response on surveillance of AFP cases and rapid supplemental vaccination, including subnational vaccination programmes in areas with low immunization coverage.

Mudslides in southern Tajikistan

The WHO expert team has begun to assess the health needs in the southern town of Kulob, after heavy rainfall caused mudslides and floods, leaving at least 15 people dead and 40 missing. With over 1000 houses damaged, several bridges destroyed and the infrastructure crippled, thousands of families have been forced to leave their homes. The first round of the polio vaccination in Kulob was reportedly completed before the flooding began, with coverage of over 90%. WHO is in contact with Tajik authorities to alleviate the health impact of the disaster, and will seek to ensure that children under 6 living in the area receive their further doses of vaccine.

Assistance in the field

WHO’s international team of epidemiologists, medical doctors, communications specialists and logisticians has worked for four weeks to conduct the outbreak investigation and to support immunization campaigns. WHO works in close partnership with UNICEF, the Centers for Disease Control and Prevention (CDC) in the United States of America, the International Federation of Red Cross and Red Crescent Societies and Save the Children International, and receives financial support from Rotary International, the United States Agency for International Development (USAID) and the Department for International Development (DFID), United Kingdom.

On 6 May, the WHO team travelled to Tajikistan’s northern district of Ayni to investigate outbreak preparedness and response, and to monitor the local vaccination campaign. Team members spoke to several local health workers, parents and teachers and concluded that the population understood the importance of following through with all three rounds of the immunization programme.

A chief doctor at the central paediatric hospital in Ayni said: “Nobody has refused the vaccine for their children, and parents have turned up en masse at the local health centres and immunization points. We needed to set up additional mobile centres in schools and in mosques. We have started sending mobile teams to remote areas.”

Prevention and preparedness in neighbouring countries

WHO is working closely with the governments of Tajikistan’s neighbours in the WHO European Region (Kazakhstan, Kyrgyzstan, Turkmenistan and Uzbekistan) on preparedness and response measures. With UNICEF and CDC, WHO has deployed expert teams to Kyrgyzstan and Uzbekistan to help strengthen surveillance and support national and subregional vaccination activities. The health ministries in Kazakhstan and Turkmenistan have formed polio task forces and are in close contact with WHO about preparedness and surveillance for cases of AFP.

In Uzbekistan, 23 AFP cases have been reported since January 2010. So far, none has been laboratory confirmed as polio infection. With its partners, WHO will help manage a two-round national polio immunization campaign aiming to reach almost 2.9 million children under 5 in Uzbekistan. On 2 May, 2010, 3.3 million doses of vaccine arrived in the country and the Government plans to start the first vaccination round on 17 May 2010.
The governments of Kazakhstan, Kyrgyzstan and Turkmenistan have strengthened surveillance and are considering vaccination campaigns. The Government of Kyrgyzstan has already begun a subnational polio immunization campaign in the areas bordering Tajikistan. WHO is conducting risk assessments to identify other WHO Member States at high risk of polio importation.