The Department of Health (DH) today (March 31) announced the latest arrangement of control and prevention strategy in response to the outbreak of measles infection emerged at the Hong Kong International Airport (HKIA).
 
     The DH launched a pilot programme for people working at the airport last Friday (March 29), under which 100 airport staff were recruited to undergo measles serology test. The aim of the pilot programme is to get an understanding of the immunity against measles among airport staff so as to identify those most in need of vaccination. The testing results revealed that among the participants, 86 per cent, i.e. 86 persons tested positive against measles antibody (IgG), revealing that they are immune to measles and no further vaccination will be required. For the remaining 14 persons, 6 were tested negative and 8 indeterminate. The DH will notify the participants individually of their serology result by phone. Vaccination will also be arranged for those with negative or indeterminate testing results.
 
     A spokesman for the DH explained, "For those who were tested indeterminate or negative, further definitive tests may reveal that they were in fact immune to measles. The testing results are considered comparable with our previous seroprevalence rates from surveillance of the population immunity before the additional definitive tests." 
 
     Further analysis of the testing results indicates that those who were born before 1967 were essentially immune to measles (100 per cent), irrespective of their place of birth. For those who were born in or after 1967, a slightly higher proportion of people who had received one or more doses of measles vaccines were immune (85 per cent) than those with unsure vaccination history or unvaccinated (81 per cent).
 
     "In view of the tight supply of measles vaccines around the globe currently and after taking into account the serology test results, the DH has decided to fine-tune the strategy of measles vaccination at the airport, with a view to reserve vaccines for people who are most in need and arrange vaccination for those who do not have sufficient immunity against measles more effective and timely," the spokesman said.
 
     The measles vaccination stations at the airport will remain open till further notice. From tomorrow (April 1) to April 4, the vaccination quota for the stations will be set at 500 doses daily and the triage system will also be enhanced. Eligible airport staff will be limited to the following target groups:

     (1) Born in or after 1967; and have not received two doses of measles vaccination; and have not been infected with measles before; and with evidence of living with infants under one-year-old or living with pregnant women; or

     (2) Have laboratory evidence of testing not positive against measles antibody (IgG)

     Details of evidence are as follows:

(a) Supporting documents for living with infants under one-year-old: for example birth certificate, discharge summary, vaccination card of the infant
(b) Supporting documents for living with pregnant women: for example, positive pregnancy test or antenatal follow-up card of the pregnant women
(c) Supporting documents for laboratory evidence: for example blood results from the DH’s measles serology test or any laboratory within the past 12 months
 
     The vaccination arrangement at the airport vaccination stations are as follows:
 

Venue:	Port Health Office Health Post (South Arrival Apron Passenger Vehicle Lounge, Level 4, Terminal 1)
	Multi-function Room, HKIA Tower (Level 5, Terminal 2)
Hours:	April 1 to 4 10am to 1pm 2pm to 5pm 6pm to 9pm

 
     The spokesman reiterated that for airport staff who do not belong to the target groups, there is no pressing need for them to receive measles vaccination and resources should be reserved for those in most need.
 
     In addition, the DH will continue with the provision of measles serology test service for airport staff belonging to target group (1) to identify those who need measles vaccination. The DH will provide blood test service to around 100 airport staff daily from April 1 to 4.
 
     The blood test station is located at the south side before Immigration Hall at Level 3 of Terminal 2 (non-restricted area). The station will be opened from 10am to 1pm and 2pm to 4pm. The DH will notify the participants individually of the serology result by phone.

     The DH anticipates that the measles outbreak at the airport will not be concluded in the near future, hence the control measures including vaccination and blood testing services will continue for a period of time till further notice. Detailed arrangement will depend on the latest situations and will be announced in due course.
 
     Meanwhile, the CHP of the DH is today investigating an additional case of measles infection, who is a worker at the airport. The 23-year-old man, without underlying chronic illness, developed fever on March 24, diarrhoea on March 27 and rash on March 28. He consulted private doctors during March 25 to 29. He sought medical attention at the Accident and Emergency Department at Princess Margaret Hospital on March 29 and was admitted for treatment. A laboratory test of his respiratory specimen was positive for measles virus. He is in a stable condition. He reported to have measles vaccination. He travelled to Shenzhen during the incubation period but had no travel history during the communicable period. He did not have contact with measles patients during the incubation period. His home contacts have remained asymptomatic so far and have been put under medical surveillance.
 
ýÿ     Upon notification of the case, the CHP immediately commenced epidemiological investigations and conducted relevant contact tracing. Initial investigations revealed that no contact has shown measles-related symptoms so far. The public places the patient visited during the communicable period are listed in the appendix.

Ends/Sunday, March 31, 2019
Issued at HKT 18:35

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