Lola Malone, MPH student Walden University PH 6165-3 Dengue fever in New Caledonia: Protect your environment to protect your health. Lola Malone, MPH student Walden University PH 6165-3 Instructor: Dr. Donald Goodwin Summer Quarter, 2009

Dengue Fever in New Caledonia Protect your environment to protect your health. Welcome! The overarching purpose of this presentation, Dengue fever in New Caledonia: Protect your environment to protect your health, is to inform and educate the citizens of New Caledonia on a growing public health problem in their community as well as incite them to action in adopting preventive measures against the spread of dengue fever.

Key Learning Goals Identify symptoms of dengue fever. Understand how dengue fever is transmitted. Identify the vector that spreads dengue fever in New Caledonia. Understand that control or elimination of vector breeding sources is a key component to prevention. Be able to implement environmental and other precautionary measures that help to control the spread of dengue fever. By the end of the presentation, citizens of New Caledonia should be able to identify the symptoms of dengue fever and how dengue fever is transmitted. It is especially important that citizens are able to identify the vector that passes on the dengue fever viruses to humans. Citizens should also gain the understanding that the most effective way to prevent dengue fever is through the continual elimination or control of vector breeding sources. These sources will be discussed in the presentation, and citizens should be able to implement simple environmental practices to control the spread of dengue fever. Other precautionary measures will be discussed briefly.

Key Learning Goals Understand the scope of dengue fever worldwide and in relation to New Caledonia. In addition, citizens of New Caledonia should understand the scope of dengue fever worldwide and in relation to their community. Figure 1 depicts the rapid re-emergence of dengue fever worldwide. As you can see, the yellow color depicts the spread of dengue fever prior to 1960. The red color shows the spread of dengue fever after 1960 (WHO, 2009a). This illustration shows the urgent need to implement effective strategies to control the spread of dengue fever and prevent further degradation of quality of life for those communities affected, including New Caledonia. Figure 1. WHO. Spread of dengue fever worldwide. Yellow color depicts spread prior to 1960. Red color depicts spread after 1960.

What is dengue fever ? Dengue fever is a mosquito-borne disease, caused by four virus serotypes. Symptoms are flu-like, typically not severe, and can last 2-7 days: rash fever headache nausea muscle and joint pain (WHO, 2009b). Immunity is not guaranteed (Phillips, 2008, pg. A 384). Dengue fever is a mosquito-borne disease caused by four virus serotypes. Symptoms of dengue fever are flu-like in nature and are typically not severe. Symptoms can last two to seven days and include a rash, fever, headaches, nausea, muscle and joint pains (WHO, 2009b). Immunity from one dengue virus serotype does not guarantee immunity from the other three serotypes (Phillips, 2008, pg. A 384).

What is dengue hemorrhagic fever (DHF) ? Dengue hemorrhagic fever (DHF) is the most severe type of dengue fever, which in addition to typical symptoms, can result in: bruising, bleeding of gums, nose and internal bleeding circulatory failure death (CDC, 2005). Increased risk of DHF when a person previously infected with one dengue virus serotype becomes infected with another (Phillips, 2008, p. A 384). Although dengue fever symptoms are typically mild, dengue hemorrhagic fever can result in some cases. Dengue hemorrhagic fever has severe symptoms in addition to the typical symptoms. Bruising, bleeding of gums and nose, internal bleeding, circulatory failure and death can occur (CDC, 2005). A person’s risk to dengue hemorrhagic fever increases when that person has previously been infected with one dengue virus, recovers and then becomes infected with another dengue virus serotype (Phillips, 2008, p. A 384).

How does a person get dengue fever? Female Aedes aegypti mosquito. Feeds during the day, rests in homes (CDC, 2008). Telltale markers include white stripes on legs and white markings on body (Mortimer, 1998). The four dengue virus serotypes are commonly spread through the bite of an infected female Aedes aegypti mosquito that passes the virus on when it bites an uninfected person. This particular mosquito typically bites during the daytime and prefers to rest in homes and other buildings, which likely increases a person’s risk to infection (CDC, 2008). Figure 2 depicts a photograph of a female Aedes aegypti mosquito feeding on a human. As you can see, the mosquito’s belly becomes engorged with blood as it feeds (Gathany, 2006). Some of the telltale markers of the this mosquito include the white stripes on its legs and white markings on its body (Mortimer, 1998). Figure 2. Gathany, J. Female Aedes aegypti mosquito feeding on human host.

How does a person get dengue fever? One Aedes aegypti mosquito can infect up to 10 people with dengue fever because of feeding habits (Jones & Mabbett, 2009, p. 13). Dengue fever is not contagious. It requires a vector. Dengue virus circulates in human blood up to 7 days (WHO, 2009b) The Aedes aegypti is an efficient transmitter of the dengue virus serotypes. It prefers to feed on multiple people. In fact, one mosquito can infect up to ten people (Jones & Mabbett, 2009, p. 13). Dengue fever is not contagious. It requires a vector, in this case the Aedes aegypti mosquito, to spread the virus from person to person. Dengue fever viruses typically circulate in the blood of an infected person for up to seven days. This time period enables the virus to infect the mosquito when it feeds on the blood of an infected person. Once infected, the mosquito can continue to infect other humans during its lifespan (WHO, 2009b).

How does dengue fever affect me? Worldwide, approximately 2.5 billion people are at risk (WHO, 2009c). Communities living in tropical and sub-tropical regions. Urban areas in these regions are at high risk (Phillips, 2008, p. A 384). Citizens of New Caledonia There has been a resurgence of dengue fever in the last few years. Worldwide, approximately 2.5 billion people are at risk (WHO, 2009c). Communities that are most at risk include those living in tropical and subtropical regions. Urban areas in these regions are particularly at high risk, where human activity has led to an an increase in potential breeding sources for the Aedes aegypti mosquito. These activities have given way for more opportunities for dengue fever to be spread (Phillips, 2008, p. A 384). New Caledonia, too, lies in a tropical region of the world where climate conditions allow the Aedes aegypti mosquito to thrive, and as a result dengue fever is on the rise in your community.

How does dengue fever affect me? Increase in dengue fever incidence in New Caledonia since September 2008. As of June 15, 2009, 8, 417 dengue fever cases and 1 death reported (WHO, 2009d). Prevalence of both DEN-1 and DEN-4 virus serotypes increases risk to DHF (WHO, 2009b). No vaccination. The incidence of dengue fever has steadily increased in New Caledonia since September 2008. As of June 15, 2009, the World Health Organization reported 8, 417 cases of dengue fever and one death (WHO, 2009d). Moreover, the prevalence of both DEN-1 and DEN-4 virus serotypes in New Caledonia increases risk to dengue hemorrhagic fever, which can, if not identified and treated in a timely manner, can lead to death (WHO, 2009b). Adding to this issue is the fact that there is currently no vaccination for dengue fever. Therefore, it is important to look to other measures of disease control in New Caledonia.

Protect your environment Requires little water to lay Aedes aegypti eggs. Typically lays eggs in still, fresh water sources (Jones & Mabbett, 2009, p. 10). Eggs turn black in color after they have been laid (Mortimer, 1998). Figure 3. CDC. Aedes aegypti mosquito eggs in a container. It is important to be able to identify where Aedes aegypti mosquitoes breed and what their eggs look like in order to implement effective control measures. The Aedes aegypti mosquito needs very little water to lay its eggs. This mosquito typically lays its eggs in still, fresh water, but there is a growing evidence that it may also lay its eggs in slightly polluted water (Jones & Mabbett, 2009). Figure 3 shows a photograph depicting Aedes aegypti mosquito eggs in a glass container (CDC, n.d.). They are small and look like accumulated dirt floating on top of the water. This photograph provides a good visual for identifying existing mosquito sources where eggs have been laid. Figure 4 is a close-up of Aedes aegypti mosquito eggs (CDC, 1982). These eggs turn to black from a white color soon after they have been laid (Mortimer, 1998). Figure 4. CDC. Close up of Aedes aegypti mosquito eggs.

Protect your environment Monitor environment around you for standing water, including: your home workplace other public spaces Increase surveillance after heavy rainfall and hot weather. Frequent surveillance needed as it only takes 2 weeks for Aedes aegypti to fully develop (Jones & Mabbett, 2009, p. 12). The main prevention method of dengue fever in New Caledonia lies in the ability to identify and eliminate existing and potential mosquito breeding sources. A reduction in mosquito population numbers means a reduction in chances of dengue fever infection. Monitor the environment around you. Look around your home, place of employment and other public spaces you frequent for areas where standing water may accumulate. Be especially mindful of your environments after heavy rainfalls and hot weather. These climate conditions can contribute to an increase in Aedes aegypti populations. Because it only takes two weeks for the Aedes aegypti mosquito to fully develop, it is extremely important that monitoring of your environment is done so on a continual basis (Jones & Mabbett, 2009, p. 12).

Protect your environment Eliminate or control standing water sources that promote the growth of the Aedes aegypti mosquito: old tires potted plants open containers solid waste products leaky faucets (Parks & Lloyd, 2004, p. 1; Phillips, 2008, p. A384; Jones & Mabbett, 2009, p. 10-1). Once existing or potential breeding sources have been indentified, it is important that efforts are taken to eliminate or control them. Typically, breeding sources around the home and other such environments include old tires, potted plants, open containers such as barrels used for rain water collection, solid waste products including discarded cans, bottles and plastic containers and leaky faucets where standing water collects (Parks & Lloyd, 2004, p. 1; Phillips, 2008, p. A384; Jones & Mabbett, 2009, p. 10-1). Even just the slightest bit of accumulated fresh water could mean a potential breeding site for Aedes aegypti.

Protect your environment Prevention measures: Empty excess water from potted plants or reduce watering. Tightly close open containers for water collection when not in or use cover them with a screen (Parks & Llyod, 2004, p. 2; CDC, 2005). Fix leaky faucets to avoid water accumulation. There are several things you can do to help prevent Aedes aegypti mosquito population growth in New Caledonia. Empty excess water from potted plants or reduce watering of plants. In addition open containers or barrels should be tightly closed or discarded. For containers used for water collection, they should be covered with a screen to prevent mosquito entry (Parks & Llyod, 2004, p. 2; CDC, 2005). Moreover, leaky faucets should be fixed to avoid water accumulation.

Protect your environment Prevention measures: Properly dispose of old tires; pack soil in them so they cannot accumulate water (Parks & Llyod, p. 14). Recycle or properly dispose of solid waste products such as cans, bottles, plastic containers, etc. (Jones & Mabbett, 2009, p. 10) Other prevention methods include the disposal of old tires. Tires can even be packed with soil to prevent the accumulation of water if they cannot be discarded (Parks & Llyod, 2004, p. 14). In addition, it is important to recycle or properly dispose of solid waste products, including cans, bottles and other plastic containers (Jones & Mabbett, 2009, p. 10).

Protect your health Other prevention measures: Use insect repellent (20-30% DEET) Use air conditioning (CDC, 2005) Use window and door screens. Use insecticide treated window coverings or bed nets (Parks & Llyod, 2004, p.2). The previously mentioned methods to control or eliminate potential mosquito breeding sources are key to reducing the mosquito populations that spread dengue fever. Other steps are necessary to avoid those mosquitoes that are currently capable of spreading dengue fever. It is important to remember that Aedes aegypti are daytime feeders and they prefer to inhabit areas in and around the home and other structures where there are people. Precautionary steps that can be taken include the use of insect repellent with 20-30% DEET on skin and clothing. The use of air conditioning is also a deterrent for the mosquito’s bite since they prefer areas where the air is warm (CDC, 2005). Other steps include the use of window and door screens, which can be treated with an insecticide, to prevent mosquito entry into the home. In addition, the use of insecticide treated window coverings or bed nets may help aid in the prevention of mosquito bites (Parks & Lloyd, 2004, p. 2).

Summary Dengue fever is spread by the bite of the Aedes aegypti mosquito. There are four different serotypes of dengue fever. DEN-1 and Den-4 No guaranteed immunity after recovery. Exposure to more that one dengue fever virus serotype increases risk to DHF. As this presentation comes to an end, I would like to leave you with a few important points. First, dengue fever is spread primarily by the Aedes aegypti mosquito in New Caledonia. Second, there are four different serotypes of dengue fever. DEN-1 and Den-4 are prevalent in your community. It is important to remember that immunity to one dengue fever serotype does not guarantee immunity to the other. Third, exposure to more than one serotype increases your risk to dengue hemorrhagic fever, which can be fatal.

Summary You can help prevent dengue fever: Eliminate existing and potential breeding sites Personal precautions Share the information you have learned with friends and family. No vaccine for dengue fever demands other preventive measures. Remember, you can help prevent dengue fever. The identification and elimination of existing and potential Aedes Aegypti breeding sites on a continual basis is of upmost importance to dengue fever prevention in New Caledonia. In addition, it is important to take other precautionary measures to avoid being bitten, including the use of insect repellent, window and door screens and bed nets. Also, it is important to share the information you have learned with others. Community involvement is key to dengue fever prevention efforts in New Caledonia!

References Centers for Disease Control (CDC). (2008). Dengue fever. Retrieved June 18, 2009, from http://www.cdc.gov/ncidod/dvbid/dengue/index.htm. Centers for Disease Control (CDC). (2005). Dengue fever: questions and answers. Retrieved June 18, 2009, from http://www.cdc.gov/ncidod/dvbid/dengue/dengue-qa.htm. Centers for Disease Control (CDC). (1982). ID# 5129: eggs of dengue fever mosquito vector, Aedes aegypti [Photograph]. Retrieved July 13, 2009, from http://phil.cdc.gov/phil/details.asp?pid=5129. Centers for Disease Control (CDC). (n.d.). 687: eggs of Aedes aegypti in a glass container [Photograph]. Retrieved July 13, 2009, from http://phil.cdc.gov/phil/details.asp?pid=687. Gathany, J. (2006). 9261: female Aedes aegypti mosquito [Photograph]. Retrieved July 13, 2009, from http://phil.cdc.gov/phil/details.asp?pid=9261.

References Jones, O.T. & Mabbett, T. (2009). Beating the dengue carrying Aedes aegypti mosquito at its own game. Asian Environmental Technology, 13(1). Retrieved July 12, 2009, from http://ejournal.envirotech-online.com/?id=aet_feb_march_2009&page=11. Mortimer, R. (1998). Aedes aegypti and dengue fever. Micscape. Retrieved July 13, 2009, from http://www.microscopy-uk.org.uk/mag/art98/aedrol.html. Parks, W. & Lloyd, L. (2004). Planning social mobilization and communication for dengue fever prevention and control: a step-by-step guide. Retrieved July 11, 2009, from http://www.paho.org/english/ad/dpc/cd/den-step-by-step.htm Phillips, M.L. (2008). Dengue reborn: widespread resurgence of a resilient vector. Environmental Health Perspectives, 116(9). Retrieved July 7, 2009, from http://www.ehponline.org/members/2008/116-9/focus.html.

References World Health Organization (WHO). (2009a). Emergence of DEN/DHF. Retrieved July 31, 2009, from http://www.who.int/csr/disease/dengue/impact/en/index.html. World Health Organization (WHO). (2009b). Dengue and dengue haemorrhagic fever. Retrieved July 12, 2009, from http://www.who.int/mediacentre/factsheets/fs117/en/. World Health Organization (WHO). (2009c). Dengue in the western pacific region. Retrieved June 26, 2009, from http://www.wpro.who.int/health_topics/dengue/. World Health Organization (WHO). (2009d). Number of reported cases of dengue fever and dengue haemorrhagic fever (DF/DHF) in the western pacific region, by country: figures for 2009. Retrieved July 7, 2009, from http://www.wpro.who.int/NR/rdonlyres/ 3C44FCF3-78D2-4655-BBEC-046DC7E2BCBB/0/Dengue_WPRO_2009_150609.pdf.