Travel Health Alerts

Dengue cases mount in east

A recent government update on dengue fever has the total number of cases rising to 8,895 – the department of Santa Cruz recorded nearly 6,800, while the next highest infection numbers were in Beni, Tarija, La Paz and Chuquisaca. At least 29 deaths have been registered. In Peru, health emergencies have been declared in 13 regions after dengue fever cases passed the 10,000-mark and five deaths were recorded (Amazonas, Ayacucho, Cajamarca, Cusco, Huánuco, Ica, Junín, Lambayeque, Loreto, Madre de Dios, Piura, San Martín and Ucayali). And in Argentina, the number of locally-acquired dengue fever cases more than doubled in the first week of this month. Circulation of the dengue virus has been reported in Córdoba, City of Buenos Aires, Jujuy, Santa Fe, Salta and Tucumán (highest cases were recorded in the last three). Read more

Advice for travellers

Dengue is spread by Aedes mosquitoes which breed in shady areas close homes and other accommodation. They bite mainly during the daylight hours, making them difficult to avoid outdoors. Travellers should cover up with long-sleeved tops, long pants, and shoes and socks when mosquitoes are most active. Apply repellent containing an active ingredient, such as DEET, Picaridin, or oil of lemon eucalyptus (PMD) when outdoors to all exposed skin. Read more about dengue fever and preventing insect bites.

Mosquito-borne viruses circulating, MVEV death; Measles alert in NSW

A Feb 3 report from the Victorian health department on what was initially believed to the a Japanese encephalitis infection acquired in the northern shire of Buloke has been revised and now confirmed as a fatal Murray Valley encephalitis virus (MVEV) case in a lady aged in her 60s. The department warned that the risk of more human cases of MVEV and Kunjin virus is elevated (‘and it is likely that JE virus is also circulating in mosquito populations’). In related news, read NSW Arbovirus Surveillance Report to Feb 18. Read more

NSW HEALTH has issued a measles alert for passengers on two flights and also listed air terminals and bus transfers in Sydney and Canberra at specific times on Feb 14 and 15 in which people may have been exposed to the virus. An individual who had travelled in Asia was subsequently found to be infected with measles; anyone spending time in the designated sites is asked to monitor for symptoms until Mar 5. Read more

Advice for travellers

While the risk of contracting MVE is low if insect bite avoidance measures are employed, the virus can cause severe illness, even death in very rare cases. The vector mosquitoes are active at dawn and dusk, particularly in the first two hours after dark. They pass on the virus to humans after feeding on infected birds attracted to flooded wetlands. Travellers to wetland and recently flooded areas of Australia should take all measures to prevent bites. Apply an insect repellent containing DEET, picaridin, or oil of lemon eucalyptus to exposed skin when outdoors. Read more about MVE.

Nipah cases at 7 year high

The WHO published an update on Nipah virus (NiV) last week, noting cases this season had risen to 11, eight of them fatal, which is a 7-year high. Infections have been reported from seven districts across the divisions of Dhaka and Rajshahi and those infected had all consumed raw date palm sap (except one case, a secondary infection in a very young) baby. The agency deemed the risk on a national level as high due to elevated early case numbers and poor public awareness of the infection, its lack of prevention or treatment and high fatality rates, and moderate for the region. According to the WHO, one of the NiV infections reported this season is suspected of being human-to-human transmission. Read more

Advice for travellers

Avoid drinking unprocessed palm juice. Fruit bats (flying foxes) are the natural hosts of Nipah virus, and females shed the virus when pregnant or lactating. The bats perch on the jars used for collecting juice from palm or date trees, leaving contaminated saliva and droppings in the jars.  People are infected when they drink the raw juice, although it is also spread through person-to-person contact. Nipah generally occurs between December and April. Read more about Nipah virus.

Floodwater risk to public health

Residents of informal settlements are those most often unaware of the risk of leptospirosis during flooding events and the need for appropriate antibiotic therapy if exposed to contaminated waters. Leptospirosis-related deaths surged by 70 percent over the past two years in Brazil and infections are reported to have risen by just over 50 percent. Read more

Advice for travellers

Leptospirosis is spread through the urine of infected animals, typically rats. The bacterium enters the body through the mucous membranes of the eyes, nose, or mouth, as well as through broken skin. Outbreaks are typically associated with exposure to floodwaters, making leptospirosis a low risk for most travellers. Read more about leptospirosis.

Shigellosis strikes more tourists

Last week the ECDC provided an update on shigellosis cases diagnosed among returning travellers since Sept last year, confirming more than 220 cases (mainly Shigella sonnei infection) and 37 more are suspected. It was revealed that the ‘outbreak evolved rapidly during November-December 2022’, while investigations continue into the sources of transmission to the tourists from 10 EU/EEA countries, the UK and USA – ‘the most likely being foodborne (including via infected food handlers), but person-to-person transmission is also possible’. A number of co-infections with other bacterial and parasitic gastrointestinal pathogens were also flagged and some of the S. sonnei strains exhibited multi-drug resistance. Many of the infected tourists had stayed in all-inclusive resorts in the Santa Maria region, located in the south of the island of Sal. Read more

Advice for travellers

Caused by Shigella bacteria, shigellosis can result in diarrhoea, fever, and stomach cramps starting a day or two after exposure, which is usually through contaminated food. Persons with mild infections usually recover quickly, but antibiotic treatment is recommended for patients with more severe symptoms. Read more.

Global polio digest

More polio cases with a date of onset from this year were announced by the GPEI last week: in Indonesia, one circulating vaccine-derived poliovirus type 2 (cVDPV2), its second in 2023, and one from Nigeria (Zamfara). The latter also registered another three cVDPV2 cases from 2022, together with Chad (seven infections Logone Occidental, Dar Sila, Hadjer Lamis, N’djamena and Ouaddai) and the D R of Congo (six cases from Haut Lomami, Lualaba and Sud-Kivu). Read more

Advice for travellers

Poliomyelitis is a potentially serious viral illness that is spread through contact with infected faeces or saliva. The risk to travellers is generally low, however vaccination is recommended for travel to affected regions and is a requirement for travel to/from some countries. If at risk, adults should have a booster to the childhood series. More on polio.

Measles cases top 500

The Feb 16 NICD update coverning the ongoing measles outbreaks shows an increase in positive tests in the week to Feb 11, climbing to 25 percent as case numbers rose to 537 since early October last year. Most cases have been in five northern states (Limpopo, Mpumalanga, North West, Gauteng and Free State), while children aged between five and nine years make up just over 40 percent of cases overall. And in Tanzania, over the past three months 857 children from Mlele district in the SW region of Katavi have fallen ill with measles infections and 12 have died. News sources state that measles vaccination campaigns continue after being introduced some five months ago when outbreaks hit seven regions. Lastly, a MSF publication outlines the task the organisation faces as it mobilises emergency teams in the D R of Congo, responding to outbreaks that last year caused nearly 150,000 measles cases and 1,800 deaths. Read more  

Advice for travellers

Measles occurs in developing and developed countries and unvaccinated travellers are at particular risk, both in transit and during their stay. While generally benign, infection can result in severe illness or death. Travelvax Australia recommends travellers check their immunisation status for measles and other childhood diseases such as diphtheria, whooping cough (pertussis) and mumps at least 6 weeks before departure. Read more about measles.

Hospitals respond to rise in respiratory infections

Paediatric hospitals in West Bengal are reporting an increase in admissions for adenovirus, with numbers higher than usual even for this peak seasonal period over late winter and early spring. Test positivity is currently over 30 percent and the community has been advised to wear masks and avoid crowds. Read more

Invasive mosquito detected in north

A species of an invasive mosquito that inhabits urban as well as rural areas is now spreading in Kenya. First detected on the African continent in Djibouti in 2012, over the next 10 years the presence of the Anopheles stephensi mosquito was confirmed in Ethiopia, Sudan, Somalia and Nigeria, and in districts bordering six other countries (Central African Republic, Chad, Egypt, Eritrea, Libya and South Sudan). Prior to this, the species was recognised as a malaria vector in South-East Asia and the Middle East where, like Aedes aegypti (dengue vector), it can use man-made water containers as breeding habitats. The mosquito was trapped during routine surveillance carried out in Marsabit county, in northern Kenya, where hospitals reported more malaria cases than usual over the dry season. Read more

Advice for travellers

Travelvax recommends that travellers visiting malarious regions discuss their itinerary and the possible need for anti-malaria medication during a pre-travel medical consultation. More on malaria.

Dengue uptick in south

Only 13 dengue fever cases have been confirmed in the southern town of Sainte-Anne this month, but another 120 residents have sought medical assistance for dengue symptoms over the past fortnight. A cluster of cases was first identified in the tourist district of Belfond, north of Ste. Anne, and there were other sporadic detections which triggered response measures from authorities on Feb 10. Read more

Advice for travellers

Dengue fever is common in most tropical or sub-tropical regions of the world. The virus is spread by daytime-feeding Aedes mosquitoes and to avoid it and other insect-borne diseases, travellers should apply an insect repellent containing an effective active ingredient, such as DEET, Picaridin or oil of lemon eucalyptus (PMD), to exposed skin when outdoors during the day. In addition, cover up with long-sleeved tops, long pants, and shoes and socks around dawn and dusk, as well as other times when the mosquitoes are active.

Parasitic infection recorded in 7 departments

A report from the public health agency has confirmed cases of leishmaniasis, but no related deaths, in seven departments so far this year. Nine visceral leishmania infections in total were recorded from Central, Concepción, Itapúa and Paraguarí (last year there were 69 cases nationally), while Amambay, Caaguazú, San Pedro and Concepción all logged a single cutaneous leishmaniasis case (57 in 2022). Dogs are the main reservoir of the parasitic disease in Paraguay. Read more

Advice for travellers

Leishmaniasis is generally a low risk for travellers. The parasitic disease is found in parts of the tropics, subtropics, and southern Europe. There are two main forms – cutaneous and visceral – both transmitted by bites from infected sand flies. There is no vaccine or preventative medication: avoiding infection relies on avoiding sand fly bites. Read more on the disease and prevention.

Norovirus alert in NW city

Diarrhoeal infections have spiked in the wake of gatherings over the Lunar New Year in the city of Taoyuan and health officials have issued a warning on the need for enhanced hygiene measures to prevent norovirus infections. On a national level, in the first two weeks of this month, more than 330,000 cases of diarrhoea were treated in emergency departments. Read more

Advice for travellers

While it is extremely contagious, norovirus infection is generally short-lived, causing nausea, vomiting and diarrhoea, which may lead to more serious complications among young children, the elderly, and the sick. To minimise the risk, wash your hands with soap and water after using the toilet and before eating, and practice good hygiene. Read more on norovirus.