Control and Prevention of Dengue fever Malaria and Leishmania

Objectives: You students will be capable to identify the epidemiology of above arthropods transmissible infectious diseases assist the community in the prevention and control programs of the above mentioned infectious diseases.

Leishmania is a parasitic disease spread by the bite of infected a. aedes aegypti b. culex c. anopheles d. sand flies e. aedes albopictus

Dengue: The vectors Aedes aegypti and A. albopictus

Aedes Dengue fever in Saudi Arabia

The world distribution of Aedes aegypti The center of origin of A. aegypti seems to be southeastern Asia. A. a. aegypti, A. a. queenslandensis and the small dark forest type A. a. formosus like A. albopictus are all Asian. A. aegypti is distributed from northeastern US almost through Argentina. It occurs worldwise within 35 north and 35 south latitude, although in summertime A. aegypti can invade to 45 north. The world distribution of Aedes aegypti

Dengue (1999): WW Areas infested with Aedes aegypti Areas with Aedes aegypti and recent epidemic dengue

Dengue WW, 2008 Dengue

Aedes Aegypti: most common breeding places Tin cans, bottles, vases, buckets, milk cans, roof gutters, animal drinking bowls and unused toilets fairly represent containers attractive for oviposition. Tree holes, rock holes and wells are other sites. One crucial site is the standard 200-liter drum containing water for households without piped water, and these drums are often treated with a larvicide. See the sketch by José Moquillaza. Although common, bottles are not important like tires, because female mosquitoes do not prefer them. Containers can be observed directly or with ovitraps used for appropriate estimates of container preference and the size of the mosquito population. Of course, mosquito populations respond directly to rain. Aedes Aegypti: most common breeding places

Aedes aegypti adult male This mosquito is rarely found more than 100 m from its source and thus proven controllable. Perhaps the newcomer A. albopictus will also adapt so that it too will become a household mosquito, depending much on artificial breeding sites not on sylvan ones. A. albopictus, more rural than urban A. aegypti, is known through southeastern US since 1985 and through northeastern Mexico since 1989. A. albopictus carries many similar viruses like Eastern Equine Encephalitis virus, Cache Valley, Keystone, Tensaw and Potosi viruses. Aedes aegypti adult male

Aedes albopictus adult male A. ALBOPICTUS HAS WHITE MIDLINE STRIPES ON THE MESONOTUM, WHEREAS A. AEGYPTI HAS A RHOMBOIDشبه المعين OF WHITE LINES. Aedes albopictus adult male

Life cycle of Aedes Aegypti After a little rain in a few days adults may emerge. This brief emergence of perhaps a week can be from old eggs rather than from new matings. Life cycle of Aedes Aegypti

Feeding. Females feed on any vertebrate host, but prefer humans Feeding. Females feed on any vertebrate host, but prefer humans. They fly upwind following odors. The first step can be to enter a house. Blood feeding and oviposition occur mostly in the morning and in the late afternoon.

Dengue fever Clinical Picture, diagnosis, treatment Dengue virus infection Dengue fever Dengue hemorrhagic fever Dengue shock syndrome (Read the attached file)

Malaria World Malaria Day: April 25th , 2009. Malaria: plasmodium falciparum, vivax, malariae and ovale. (Read the attached file)

Map

Malaria patient

Malaria In 104 countries 300-500 million cases/year World 1.1 to 2.7 million deaths/year Africa deaths 961000 SEAR countries 53000 India 20000 KSA???

Anopheles mosquito

Group 1: 10 countries interrupted transmission: Bah, Cyp, Jor, Kuw, Leb, Lib, Pal, Tun, UAE Group 2: 4 countries targeting elimination: Egy, Mor, Oma, Syr Group 3: 4 countries low- moderate endemicity: Ira, Iraq, Pak, KSA Group 4: 5 countries high burden: Afghanistan, Dji, Som, Sud, Yem

Leishmaniasis What is Leishmaniasis? Life cycle. Mode of infection. Control and Prevention. Read also the attached file.

Leishmaniasis is a protozoal disease caused by Leishmania parasite, which is transmitted by the sand fly . Leishmaniasis is of three types ; cutaneous leishmaniasis, muco-cutaneous and the visceral (Kala-azar )

Leishmaniasis Life Cycle Sand fly Stages Human Stages 1 Sand fly takes a blood meal 8 Divide in midgut and migrate to proboscis (Injects promastigote stage into the tissue) 2 Promastigotes are Phagocytized by macrophages i 3 Promastigotes transfer into amastigotes inside macrophages 7 Amastigotes transform Into promastigote stage in midgut d Leishmaniasis life cycle 6 Ingestion of Parasitized cell 4 Amastigotes multiply in cells (Including macrophages) of Various tissues 5 Sand fly takes a blood meal i Infective stage (ingest macrophages Infected with amastigotes ) d Diagnostic stage

Leishmaniasis: Mode of infection Sand fly bite Others (infected blood transfusion and Pregnancy in (VL), physical contact in CL)

Sand fly The sand fly causes leishmaniasis.

Leishmaniasis Sand Flies are vector of the disease. More than 500 species and subspecies in the world. of which, only 35 types are known to transmit the disease, Phlebotomus in OCL, and Lutzomia in NCL. There are more than 21 Leishmanial species .

Leishmaniasis Diagnosis: Clinical features. Smear from the base of the ulcer stained with Wright‘s stain detects round or ovoid parasite in the cytoplasm of macrophages. Leishman test: Intradermal injection of leishmanial antigen causes a delayed tuberculin type of reaction.

Leishmaniasis Reservoirs The dogs in the Mediterranean countries The man in the Middle East The wild rodents in Asia and Africa

Leishmaniasis WW W O R L D Leishmaniasis Cutaneous Leishmaniasis > 12 Million people infected in 88 countries > 350 Million people are risk Annually,0.5M (VL)80,000 Deaths,1.5M(CL) D Cutaneous Leishmaniasis Visceral Leishmaniasis Mucocutaneous Leishmaniasis

Leishmaniasis Types Visceral Cutaneous Mucocutaneous * Fever * Hepatosplenomegaly * Weight loss Death, 90% in Bangladesh, Brazil, India, Nepal,and in Sudan Cutaneous Skin ulceration, 90%Afghanistan ,Syria,Iran,Iraq,Brazil,Peru, and Saudi Arabia Mucocutaneous * Skin and mucus membranes affection Might be fatal. 90% in Bolivia, Brazil and Peru

Leishmaniasis in KSA Leishmaniasis: It is known in the Kingdom back to 1950. Ministry of Health has established the leishmaniasis unit in the 1980 Under The precautionary medicine to follow-up the disease in the Saudi cities

Leishmaniasis in KSA There are VL and CL. Types There are VL and CL. VL caused by L.Donovani LON 42, and the Rattus rattus is the reservoir. 2 types of CL(ZCL and ACL) In the Riyadh and Eastern province, ZCL transmitted by P.Papatasi and caused by L.Major LON4

Leishmaniasis in KSA Cont. CL in Southern region is ACL transmitted by P.Sergenti and caused by L.Tropica LON 72

Leishmaniasis in KSA Sand flies: There are 20 types of Sand Flies in the KSA. 7 are Phlebotomous and 13 are of Sergentomyia type.

Visceral Leishmaniasis A area Northern Al-jouf Tabouk Medina Riyadh Makkah Eastern Baha Najran Aseer Jazan Affected area

Reported Cases of VL RCVL 1984-2004

Cutaneous Leishmaniasis has many local names

CL: Seasonal Variations The peak of cutaneous leishmaniasis is in August, October, December, January and February. The least number of cases are reported in May and June.

CL: Geographical Dist. 2001 N CLGD Northern Al-jouf Tabouk Hail Qaseem 8.4 % 2001 Tabouk 18.2 % 7.6 % Hail Qaseem Alhsa only 41.2 % Medina Riyadh 9.6 % Makkah Eastern Baha Najran Aseer N Jazan

CL: cont. 2004 N GD Northern Al-jouf Tabouk Hail Qaseem Medina Riyadh 9.1 % 2004 Tabouk 26.6% 18.5 % Hail 4.1 % Qaseem Alhsa 20.9% Medina Riyadh 4.1 % Makkah Eastern Baha Najran Aseer N Jazan

Reported Cases of Cutaneous L. CL 1983-2004

Reported Cases of CL CL 1983-2004

Cutaneous Leishmaniasis in Infants 1403-1424 H (Infants) Leishmaniasis usually affects children more than other age groups .

Clinical Types of CL CL Hyperkeratotic Mucosal Lymphangitis after Pentostam treatment Nodules

Clinical Types of CL. Types Recidivans Plaque Erysipeloid Lupoid/Disseminated

VBD Prevention Programs Efforts should focus on sustainable environmental control rather than eradication Control programs should be community-based and -integrated. They cannot rely solely on insecticides nor require large budgets Need to promote VBD as a priority among health officials and the general public

Community Approaches Define communities geographically More likely to be sustainable Advantages: built-in manpower, help develop resources and empower community organizations Disadvantages: more difficult to organize, take longer to get off the ground

Community Participation First must educate the public in the basics of VBD, such as: Where the mosquito lays her eggs The link between larvae and adult mosquitoes General information about VBD transmission, symptoms and TTT.

Skills Deficit Knowledge is not sufficient to produce behavior change People may lack the skills necessary to carry out the recommended behaviors Need to address this skills deficit

Barriers and Motivation (Part 1) Knowledge combined with skills still may not be sufficient to change behavior Need to understand what barriers may prevent the behavior, and what factors may motivate people to take the desired action Barriers and motivating factors vary in different regions

Barriers and Motivation (Part 2) Structural factors laws regarding Aedes aegypti habitats Environmental factors lack of potable water, need to store water inadequate solid waste disposal Attitudinal factors beliefs: causes, treatment, prevention of febrile illnesses Community factors community history and structure other priority problems in the community

Cues for VBD like Dengue Preventive Behaviors People need reminders when they are learning a new behavior Behavioral cues are prompts or signals to remind the person to engage in the desired behavior

Cues: Feedback Use regular feedback of entomologic and epidemiologic data Every time someone receives the information, it can serve as a reminder to act If the data indicate control activities are successful, they serve as positive reinforcement

Cues: Presence of Adult Mosquitoes Idea to promote: Person sees adult mosquito Asks him/herself, “Where did it come from?” Immediately searches for larval habitats Eliminates or controls all potential habitats found

Cues: Water Shortages and Rationing For locations where there are seasonal or other temporary water shortages Provide information on how to properly store water

Cues: Rainfall Link rainfall to the creation of larval habitats This mental link can remind people to look for and eliminate larval habitats after it rains Eliminates larval habitats influenced by rainfall, and perhaps others as well

The Challenge Achieve active community involvement Solicit input from the earliest program planning stages Encourage community ownership Programs that emphasize telling communities what to do, without involving them or taking their views into account, are not likely to be effective True community participation is the key

VBD Prevention Role of Vaccines: Are they available or under trials? Regional collaboration (VBD framework, WHO-EMRO) Role of Insecticide treated net ???

VBD Surveillance and Control 10

Surveillance: Goals and Objectives Provide early and precise information disease severity Predict VBD like dengue and malaria transmission and guide implementation of control measures Link clinical and entomologic surveillance 11

Vector Control Methods Chemical Control Larvicides may be used to kill immature aquatic stages Ultra-low volume fumigation ineffective against adult mosquitoes Mosquitoes may have resistance to commercial aerosol sprays 13

Vector Control Methods Biological control Largely experimental Option: place fish in containers to eat larvae Environmental control Elimination of larval habitats Most likely method to be effective in the long term

Purpose of Control Reduce female vector density to a level below which epidemic vector transmission will not occur Based on the assumption that eliminating or reducing the number of larval habitats in the domestic environment will control the vector The minimum vector density to prevent epidemic transmission is unknown 14

Programs to Minimize the Impact of Epidemics Education of the medical community Implementation of emergency plan Education of the general population 15

INSECTICIDE USE FOR VECTOR CONTROL - EMRO -

WHO SPECIFICATIONS FOR PUBLIC HEALTH PESTICIDES Only available on the Internet at WWW.WHO.INT/CTD/WHOPES

WHO Collaborating Centres for quality control of pesticides Station de Phytopharmacie, Gembloux CDC, Atlanta HEJIR Chemistry, Karachi CIPEIN, Buenos Aires

More Readings; WHO-EMRO: Country Profile: Saudi Arabia. EMRO website CDC materials and publications CDC: VBD fact sheets. Read the attached files.

Objectives: You students will be capable to identify the epidemiology of above arthropods transmissible infectious diseases assist the community in the prevention and control programs of the above mentioned infectious diseases.