Ministry of Health to buy smallpox vaccine
Ministry of Health to buy smallpox vaccine
The Ministry of Health has decided in principle to buy smallpox vaccine, as part of its planning for the remote possibility of the virus being used in a terrorist attack.
"However I cannot over-emphasise our view that any such possibility is remote. We've made this decision as part of our general preparedness for any terrorist attack, rather than because we are actively anticipating any need to use the vaccine," spokesman Dr Don Matheson said.
"We have decided in principle to buy 10,000 doses, to have on standby. This is in line with the decision made by the Australian Government and announced on the weekend," Dr Matheson, Deputy Director-General of Public Health said.
"I must also emphasise that at this stage this is a decision in principle. Further decisions, including which vaccine to buy, and when and whether it would be offered to particular groups such as frontline health workers have not been made. "
Dr Matheson said the Ministry would negotiate to buy about 10,000 doses of the vaccine . It could be in the country by March, and would be stored in a secure facility from where it could be quickly distributed if needed.
"Bioterrorism is by definition unpredictable. This is part of broader planning being undertaken by a number of agencies which are jointly considering responses to a range of possibilities. Being prepared lessens our risk."
"In all probability the vaccine will never be used. However it is our duty to protect the health of New Zealanders. In making this decision public it may be that our biggest contribution is to New Zealanders' mental health and wellbeing by providing a degree of reassurance.
Dr Matheson said internationally there were proven methods for minimising the spread of infectious diseases which included travel restrictions, isolation of infected people and intensive monitoring.
Australia announced it had bought 50,000 doses of smallpox vaccine last week, and is expecting to buy up to 100,000 more.
Questions and Answers:
What is smallpox?
Smallpox is a contagious, and sometimes fatal infectious viral disease that has existed for thousands of years. There is no specific treatment for smallpox disease. The most common form of the disease, Variola major, accounts for 90 percent of all cases, and historically this version has had an overall fatality rate of about 30%.
What are the symptoms of smallpox?
Smallpox is characterised by a sudden onset of flu-like
symptoms, including fever, backache, headache, and
occasionally abdominal pain and vomiting. Two to three
days later, a rash develops, which usually progresses into
raised bumps concentrated more on the face and limbs than on
the trunk. After about two weeks most of these turn into
scabs which fall off.
How is the virus transmitted?
Generally, direct and fairly prolonged contact is required to spread smallpox from one person to another. Smallpox can be spread through direct contact with infected bodily fluids or contaminated objects such as bedding or clothing. Rarely, smallpox has been spread by virus carried in the air in enclosed settings such as buildings, buses, and trains. Humans are the only natural hosts. Smallpox is not known to be transmitted by insects or animals.
Usually an person with smallpox becomes contagious after the onset of the rash. At this stage the infected person is usually very sick and not able to move around in the community, so the spread is limited. The infected person is contagious until the last smallpox scab falls off.
What is the history of smallpox in New Zealand?
The earliest known cases of smallpox in New Zealand were among settlers arriving in 1840, and cases continued to occur until 1925. Outbreaks in Dunedin in 1903 (four cases) and in Christchurch in 1904 (14 cases) were followed by the largest recorded smallpox outbreak in New Zealand, centred on Auckland in 1913-14. This outbreak involved more than 2000 cases, including an estimated 55 deaths. The last New Zealand smallpox outbreak occurred in Otago in 1920 involving 95 cases, and the last notified smallpox case was reported in 1925.
When was the last case of smallpox worldwide?
The last community acquired case of smallpox occurred in Somalia in 1977, and the disease was declared eradicated in 1980. After the disease was eliminated from the world, routine vaccination against smallpox among the general public was stopped because it was no longer necessary for prevention.
How safe is the vaccination?
There are side effects and risks associated with the smallpox vaccine. Most people experience normal, usually mild reactions that include a sore arm, fever, and body aches. However, other people experience reactions ranging from serious to life-threatening.
People most likely to have serious side effects are:
people with skin conditions (especially eczema or atopic dermatitis)
people with weakened immune systems, such as those who have received a transplant, are HIV positive, are receiving treatment for cancer, or are currently taking medications (like steroids) that suppress the immune system
women who are pregnant or breastfeeding
children under 12 months
anyone who would suffer an allergic reaction to the vaccination
In the past, about one in 10,000 vaccinated for the first time experienced reactions that, while not life-threatening, were serious. Between 14 and 52 people out of every 1 million people vaccinated for the first time experienced potentially life-threatening reactions to the vaccine. Based on past experience, it is estimated that 1 or 2 people in 1 million who receive the vaccine may die as a result, but latest research estimates the figures could go higher.
How effective is the vaccine?
Smallpox vaccination provides high level immunity for 3 to 5 years and decreasing immunity thereafter. If a person is vaccinated again later, immunity lasts even longer. Historically, the vaccine has been effective in preventing smallpox infection in 95% of those vaccinated. In addition, the vaccine was proven to prevent or substantially lessen infection when given within a few days of exposure.
Vaccination alone will not control an outbreak. Other
measures including isolation and close monitoring are needed
on top of this to properly control any outbreak.