Author: Dr. Sukheshni Nand (Bachelor in Dental Surgery)
Measles is a highly contagious airborne disease, which spreads easily through the coughs and sneezes of infected people [3]. The most effective method of preventing transmission of the virus is through measles vaccination. Initial symptoms of this virus (prodrome) generally consist of fever, malaise, cough, conjunctivitis, and coryza [7]. According to WHO, Measles has a long incubation period with the average time from exposure to onset of early symptoms of about 10 - 12 days and from exposure to rash onset an average of 14 days (with a range of 7- 23 days) [7]. The 2019 measles outbreak largely affected the four pacific island countries, namely Samoa, Tonga, Fiji, and American Samoa.
Population movement is a large factor in the spread of measles [6]. Countries experiencing the regular movement of tourists or overseas workers, in particular those traveling to and from measles-affected countries, are at risk for introduction of measles, and countries with district and local level immunization coverage below 95% are vulnerable to outbreaks [6]. Given that many PICs are popular tourist destinations, the risk of a measles outbreak is high. Infants, populations with poor access to health care services, and co-morbidities such as malnutrition, including Vitamin A deficiency are more vulnerable to infection and at higher risk for severe disease [6].
Samoa had reported 5,552 measles cases as of 22 December 2019 with 79 measles-related deaths [1]. Following this outbreak, Samoa passed a law on making measles vaccination compulsory (binding law into effect on 1 January 2020: “Law of Love”). The outbreak reached its post-peak by the end of 2019 with the number of cases per day decreasing [1]. Tonga identified 592 confirmed cases of measles with zero measles-related deaths, as of 23rd December 2019 [1]. The situation is now stable; Tonga is seeing a 5th wave of measles transmission [1]. On 13th December, Tonga investigated thousands of faulty measles vaccines (as a result of the vaccines being either poor quality or were incorrectly stored) [4]. Over 20,000 people were re-vaccinated after people with measles were found to have received both vaccine doses [4]. Fiji had reported 25 confirmed measles cases with no measles-related deaths by the end of 2019 [2]. Once the outbreak was declared, a mass vaccination campaign was conducted and more than 200,000 people in Fiji were immunized against measles, with the current 98% coverage in the Central Division [1]. The 3rd wave of the targeted vaccination campaign, extended to all divisions, continued aiming for over 90% coverage by 24 December 2019 [1].
American Samoa declared 10 confirmed cases with no measles-related deaths on the 8th of December 2019 [1]. Kiribati had also identified one laboratory case of measles, which triggered the introduction of MR zero dose and the defaulter tracing campaign started on Friday 20 December in outer islands [1].
In efforts to combat this virus, WHO intensified measles surveillance to ensure measles cases were rapidly detected and public health measures implemented [6]. In addition, UNICEF will send two ice-lined refrigerators to Tonga to ensure that the vaccines are properly stored [1]. WHO helped Samoa’s health system recover by delivering vaccines and provided appropriate management of post-measles infections [1]. UNICEF has made efforts to identify coordination and leadership structures, mechanisms for preparedness, rapid response, and lines of communication between local level, sub-national, and national level in all 13 countries [6]. Additionally, UNICEF had scheduled to deliver MMR vaccines and Vitamin A to all affected Pacific Island countries, including the Cook Islands, Federated States of Micronesia, Nauru, Niue, Solomon Island, and Tuvalu [1].
In an effort to strengthen response and preparedness in the Pacific, WHO and UNICEF continue to work with other partners such as CDC, SPC, and Global Outbreak Alert and Response Network (GOARN) [1]. All partners work to ensure contingency for human resources, available stocks of vaccine and injection devices, and operational funds are accessible to support rapid outbreak investigation and response immunization if measles cases are detected again [6]. Furthermore, the WHO also continues to work with Pacific Island countries and regional partners to update measles risk assessments for countries with immunity gaps and those with limited response capability [1].
Control and management of measles is challenging, as the disease is highly contagious and can be transmitted by coughing and sneezing or direct face-to-face contact. To prevent further outbreaks, we need to raise public awareness, ensure vaccine uptake is encouraged at every available opportunity, and encourage good hygiene. People diagnosed with measles need to be isolated immediately from the public after the onset of a measles rash. Health Protection services are in the frontlines of disease control and prevention. Therefore, routine measles vaccination and the provision of Vitamin A for children, combined with mass immunization campaigns in the Pacific Island countries are key public health strategies to reduce measles outbreaks.
Reference
Joint WHO/UNICEF Measles Outbreak Response and Preparedness in the Pacific. MEASLES OUTBREAK IN THE PACIFIC - SITUATION REPORT No. 8. 2019
Ministry Of Health and Medical Services. Measles Outbreak: 25 Confirmed Cases of Measles in Fiji. 2019.
Ministry of Health and Medical Services. Measles Media release No.8. 2019
RNZ News. Tonga and health agencies to investigate faulty measles vaccines. 2019.
The Fijian Government. Media Centre. Measles 16th November 2019.
World Health Organisation. Disease Outbreak News. Measles – Pacific Island Countries and Areas. 2019
World Health Organisation. Measles. Vaccine-Preventable Diseases Surveillance Standards. 2018