Health blogs are becoming increasingly popular among the health care workers and public. It serves as an informal interface to exchange and argue about current health issues. Information is plenty, especially at this stage with most people accessing internet for their day to day updates and we feel it is necessary to critique and synthesis the available information.

This health blog will serve several purposes, including discussions about current health issues, an informal environment for staff and students to interact, an opportunity for the current students to know what’s happening in the school. We are also planning to interview several alumni students of the school who are currently occupying key positions in health sector, who could serve as mentors for the current students.

We are starting this health blog with the discussion about the recent swine flu outbreak in Mexico, which has rapidly spread into other parts of the world.

WHO has declared a ‘public health emergency of international concern’ after the recent Swine flu outbreak in Mexico and has increased the pandemic alert system to Phase 4.

More than 1300 cases have been reported or suspected in Mexico and the south-western United States and more than 100 estimated deaths localised to Mexico, but only 20 laboratory confirmed as a novel swine flu strain. Most of the deaths have been occurring among young healthy adults. Countries around the world are on high alert after the outbreak, with some imposing travel and import restrictions.

Padmanesan Narasimhan, a PhD student talks to Prof Raina MacIntyre, an expert on Influenza outbreaks on this issue.

Interview with Prof Raina MacIntyre

Could you tell us briefly about the nature of swine flu and how does it differ from other flu outbreaks in the past?
It is influenza type A, HIN1, which has arisen from a reassortment of swine, avian and human strains. It appears to have spread from human to human around the world fairly quickly, and in Mexico has a high case fatality rate and appears to affect healthy young adults disproportionately.

People who died were mostly of young age, is this something characteristic of the flu outbreaks?
No, most flu outbreaks are characterised by higher morbidity and mortality in the very old and the very young. This pattern (of high rates of death and severe illness in healthy young adults) was seen in the 1918 pandemic, and is thought to be due to the phenomenon of “cytokine storm”, which is an aggressive response of the immune system to the infection.

The WHO has increased the pandemic flu alert to level 4, what does that mean? Could it get worse?
Yes, but phase 4 does not mean a pandemic is inevitable – just that it is possible.

In developing countries and less developed countries there are numerous interactions with pigs and humans, is that something to worry about?

Yes, but it is a concern for the development of a new influenza strain. In this case, that has already occurred. However, we traditionally think of a pandemic as arising when a new H type (such as H5 or H7) emerges in humans. This is called antigenic shift. This virus has a known H type, H1, but is drifted enough to have pandemic potential.

What do you think are the best ways to prevent flu outbreaks, especially for outbreaks of this nature?
We rely on multiple measures used simultaneously or in sequence, categorised into pharmacological and non-pharmacological measures. The former include vaccine and antivirals. Vaccines take 8-12 weeks to develop, and we currently do not have a matched vaccine. We should have one within a few months. The virus appears to be sensitive to the neuraminidase inhibitor class of antivirals, which would be a first line measure for both treatment and prophylaxis. Non-pharmacological measures include social distancing (such as school closure, quarantine), handwashing, face masks, and other infection control measures.

What measures/precautions the public should be aware of?
If a pandemic is declared and affects Australia, simple measures like avoiding crowded places, seeking medical assistance if symptomatic (which may include receiving antivirals), staying away from work if sick, should be employed. Handwashing and face masks are easily available measures that will protect against infection. People should get vaccinated with the seasonal vaccine and with the matched vaccine.

Raina MacIntyre is an expert on Influenza outbreaks and is the head of School of Public Health and Community Medicine, UNSW. She can be contacted at R.MacIntyre@unsw.edu.au