Beyond hand sanitiser: What the latest norovirus outbreak can teach travellers

 

WHEN news emerged of a norovirus outbreak aboard the Caribbean Princess cruise ship, many Malaysians may have paid little attention. Stomach bugs contracted while travelling are often dismissed as routine food poisoning or a minor inconvenience that resolves within a day or two.

However, the outbreak, which affected more than 100 passengers and crew members, serves as a useful reminder that not all gastrointestinal infections behave in the same way, nor can they all be prevented using the habits many people adopted during the COVID-19 pandemic.

Norovirus, sometimes referred to as the “winter vomiting bug”, is highly contagious and spreads rapidly in crowded environments such as cruise ships, hotels, schools, hospitals and care homes.

What makes it particularly challenging is that only a very small number of viral particles are needed to cause infection. A person may feel perfectly well in the morning and then develop sudden vomiting and diarrhoea within hours.

For most healthy adults, the illness resolves within one to three days. However, the rapid onset of symptoms and the risk of dehydration can make the infection particularly unpleasant, especially for children, older adults and individuals working or travelling in hot environments.

Although large norovirus outbreaks are uncommon in Malaysia, increasing international travel means imported cases remain possible.

Cruise holidays are becoming increasingly popular among Malaysians, particularly on regional routes involving Singapore, Phuket, Penang and Langkawi.

Large gatherings associated with Umrah, Haj and overseas travel can also increase exposure to infectious diseases that may be less familiar locally.

(Image: Unsplash/Fusion Medical Animation)

One reason norovirus often catches people off guard is that it behaves differently from the bacterial food poisoning many Malaysians are more familiar with.

Bacterial infections caused by organisms such as Salmonella may involve fever, abdominal cramps, or blood and mucus in the stool, with symptoms often lasting several days.

Norovirus, by contrast, tends to strike suddenly. Vomiting is often the most prominent symptom, fever is usually mild or absent, and recovery is generally quicker.

The other important difference lies in prevention.

During the COVID-19 pandemic, many people understandably became accustomed to relying heavily on alcohol-based hand sanitisers.

While sanitisers remain useful against many infections, norovirus is more resistant because of its protective outer structure. Alcohol alone may not remove the virus effectively from the hands.

For norovirus, thorough handwashing with soap and running water remains the most reliable defence. The process is just as important as the soap itself because the virus must be physically washed away from the skin.

This is particularly important before eating, after using the toilet and when caring for someone who is unwell.

Cruise ships, unfortunately, provide ideal conditions for norovirus transmission. Thousands of passengers share dining facilities, toilets, lifts, handrails and recreational spaces within relatively confined environments.

The virus can spread through contaminated food, surfaces, direct contact with infected individuals and even droplets released when someone vomits nearby.

This does not mean Malaysians should avoid cruise holidays altogether. The risk can be reduced significantly through simple precautions.

Travellers should prioritise handwashing, exercise caution when consuming raw or undercooked shellfish, avoid unnecessarily sharing eating utensils and seek medical attention early if symptoms develop.

Anyone experiencing vomiting or diarrhoea should avoid crowded dining areas and minimise close contact with others until fully recovered.

(Image: Unsplash/Murat Ts)

At home, norovirus can continue spreading if proper cleaning measures are not followed. The virus is capable of surviving on surfaces such as taps, toilet handles, remote controls and doorknobs for extended periods.

Household members caring for an infected individual should pay particular attention to hygiene practices, especially in shared bathrooms and kitchens.

Hydration is also critical. Oral rehydration salts, readily available at pharmacies, are generally more effective than sugary drinks or plain water alone in replacing lost fluids and electrolytes.

Medical attention should be sought if a person is unable to keep fluids down, becomes unusually weak or confused, or develops signs of severe dehydration.

Importantly, antibiotics are ineffective against norovirus because it is caused by a virus rather than bacteria.

Malaysia has not reported any major norovirus outbreaks at present. Nevertheless, awareness remains important as international travel continues to increase.

Public health preparedness is not only about responding to major outbreaks, but also about understanding the simple measures that help prevent transmission before problems arise.

In an era of advanced medicines and increasingly sophisticated healthcare systems, one of the most effective defences against norovirus remains remarkably simple: washing your hands properly with soap and water. 

Dr Muhammad Amir Yunus is a molecular virologist at the Pusat Kanser Tun Abdullah Ahmad Badawi (PKTAAB), Universiti Sains Malaysia (USM).

The views expressed are solely of the author and do not necessarily reflect those of  MMKtT.

- Focus Malaysia.