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File: 123096_08071515_90_0001.txtSUBJECT: AFMIC SPECIAL WEEKLY WIRE 34-90A [b.2] [b.2] UNCLAS 1. THIS SPECIAL WIRE IS INTENDED TO PROVIDE CLARIFICATION AND FURTHER DISSEMINATION OF MEDICAL INTELLIGENCE ON A SUBJECT OF CURRENT INTEREST. 2. DESERT SHIELD: SANDFLY FEVER AND LEISHMANIASIS THREAT ALTHOUGH SAND FLY-BORNE DISEASES ARE THE MOST PREVALENT VECTORBORNE DISEASE THREATS IN THE REGION, THE OVERALL RISK IS LOW TO MODERATE, DEPENDING ON LOCATION. THE FOUR REPORTED SAND FLY-BORNE DISEASES INTHE AREA, PRIORITIZED IN ORDER OF PROBABLE OCCURRENCE, ARE CUTANEOUS LEISHMANIASIS (RURAL WET TYPE AND URBAN DRY TYPE), SANDFLY FEVER, AND VISCERAL LEISHMANIASIS. THE RISK OF NONINDIGENOUS PERSONNEL ACQUIRING THESE DISEASES IS EXPECTED TO INCREASE IN PROPORTION TO LENGTH OF STAY IN THE REGION. THE TWO TYPES OF CUTANEOUS LEISHMANIASIS ARE APT TO CAUSE THE GREATEST LOSS OF MAN-DAYS. THE OCCURRENCE OF CUTANEOUS LEISHMANIASES IS HIGHLY FOCAL, DESPITE RATHER BROAD DISTRIBUTION. THE DISTRIBUTION OF SAND FLY-BORNE DISEASES, INCLUDING LEISHMANIASIS, PRIMARILY DEPENDS ON THE DISTRIBUTION OF THE VECTOR AND RESERVOIR HOSTS. SAND FLY DISTRIBUTION OCCURS IN A BELT ABOUT 250 MILES WIDE ACROSS SAUDI ARABIA. THIS BELT CENTERS AROUND JEDDAH ON THE WEST COAST, BROADLY ENCIRCLES RIYADH, AND EXTENDS TO DAMMAN ON THE EAST COAST. SAND FLY DENSITY GENERALLY IS HIGHEST ON THE WEST COAST AND LOWEST ON THE EAST COAST. OTHER ENDEMIC AREAS INCLUDE RURAL KUWAIT, MOST OF IRAQ (EXCEPT FOR THE SOUTHWESTERN BORDER WITH SAUDI ARABIA), NORTHERN JORDAN, AND ALL OF ISRAEL AND IRAN. THE RURAL FORM OF THE DISEASE, CAUSED BY LEISHMANIA MAJOR, PRODUCES WET, ULCERATED SORES (OFTEN ONLY ONE) 1 TO 6 WEEKS AFTER AN INFECTIVE SAND FLY BITE. THE SORE NORMALLY SELF-RESOLVES, BUT MAY BECOME CHRONIC IF UNTREATED. GERBILS AND FAT-TAILED RATS ARE THE PRIMARY RESERVOIRS OF THE DISEASE. THE DISEASE, ALTHOUGH DECLINING IN RECENT YEARS, MAY INCREASE RAPIDLY IF RODENTS PROLIFERATE AROUND SOLID WASTE DISPOSAL AREAS LOCATED CLOSE TO HUMAN ENCAMPMENTS. AN INCREASED INCIDENCE IN RECENT YEARS OF THE DRY, URBAN FORM OF CUTANEOUS LEISHMANIASIS, CAUSED BY L. TROPICA, HAS BEEN ASSOCIATED WITH A HIGH INCIDENCE IN NONIMMUNE FOREIGN WORKERS. HUMANS AND DOGS ARE THE PRIMARY AND SECONDARY RESERVOIRS, RESPECTIVELY. AN INCUBATION PERIOD UP TO SEVERAL MONTHS FOLLOWS AN INFECTIVE SAND FLY BITE, WHEREUPON THE PARASITE PRODUCES MULTIPLE DRY CIRCUMSCRIBED LESIONS (CALLED ORIENTAL SORES OR ALEPPO SORES) THAT OCCASIONALLY SELF- RESOLVE, BUT MORE OFTEN BECOME CHRONIC, WITH RESULTING DISFIGURING SCARS. SANDFLY FEVER IS A VIRAL DISEASE THAT MAINLY AFFECTS CHILDREN AND NONIMMUNE NONINDIGENOUS PERSONNEL. SANDFLY FEVER DISPLAYS INFLUENZA- LIKE SYMPTOMS (MINUS RESPIRATORY SIGNS) WITHIN 3 TO 4 DAYS OF AN INFECTIVE SAND FLY BITE. THE DISEASE IS SELF-LIMITING (FATALITIES ARE UNKNOWN), AND COMPLETE RECOVERY GENERALLY OCCURS WITHIN 3 TO 5 DAYS. SANDFLY FEVER CASES ARE REPORTED ONLY IN A FEW FOCI ALONG THE WEST COAST IN SAUDI ARABIA, BUT POTENTIAL RISK EXISTS IN ALL AREAS REPORTED TO HAVE SAND FLIES (SEE CUTANEOUS LEISHMANIASIS AREAS ABOVE), WITH GREATER RISK IN NEARLY ALL COUNTRIES SURROUNDING SAUDI ARABIA, INCLUDING IRAQ, JORDAN, ISRAEL, KUWAIT, AND EGYPT. IN EGYPT, WHERE FOCI ARE INTENSE, THE DISEASE MAY SPREAD RAPIDLY THROUGH NONINDIGENOUS FORCES, WITH POTENTIAL OPERATIONAL DEGRADATION IF LARGE PERCENTAGES OF PERSONNEL ARE INFECTED CONCURRENTLY. VISCERAL LEISHMANIASIS (OR KALA-AZAR), CAUSED BY L. INFANTUM, OCCURS SPORADICALLY THROUGHOUT THE REGION. THE DISEASE IS CHARACTERIZED BY A 2 TO 4 MONTH INCUBATION PERIOD, SEVERE DAILY BIMODAL FEVER SPIKES, AND GRADUALLY INCREASING HEPATOSPLENOMEGALY, LYMPHADENOPATHY, EMACIATION, AND WEAKNESS. IF UNTREATED, VISCERAL LEISHMANIASIS MAY BE FATAL WITHIN WEEKS. ALTHOUGH IT IS CONSIDERED A CHILDHOOD DISEASE IN THE REGION, NONIMMUNE NONINDIGENOUS PERSONNEL COULD BE SUSCEPTIBLE. DOGS ARE THE MOST COMMON RESERVOIR HOST. VISCERAL LEISHMANIASIS OCCURS IN FOCAL AREAS OF EXTREME SOUTHWESTERN SAUDI ARABIA, THROUGHOUT ISRAEL, WESTERN JORDAN, AND CENTRAL, EASTERN, AND NORTHERN IRAQ. KUWAIT IS FREE OF THE DISEASE. MOST DISEASE TRANSMISSION IS EXPECTED DURING PERIODS OF GREATEST SAND FLY ABUNDANCE (GENERALLY JUNE THROUGH AUGUST), ALTHOUGH LONG INCUBATION PERIODS FOR LEISHMANIASIS MAY CAUSE A PROTRACTED PEAK ONSET OF CASES FROM OCTOBER TO FEBRUARY. DELAYED ONSET OF CASES MANDATES THAT PREVENTIVE ACTIONS MUST OCCUR WELL AHEAD OF CLINICAL CASES IF OUTBREAKS ARE TO BE AVOIDED. THE PRINCIPAL SAND FLY VECTORS ARE PHLEBOTOMUS PAPATASI AND P. SERGENTI. P. SERGENTI LIVES IN RODENT (PRIMARILY GERBIL) BURROWS, WHILE P. PAPATASI BREEDS IN EARTHEN OR WOODEN STRUCTURES, WHERE HUMIDITY IS HIGH. SAND FLIES CAN READILY PENETRATE MOSQUITO NETTING, SO PREVENTION OF EXPOSURE TO FLY BITES AFFORDS THE BEST PROTECTION AGAINST SAND FLY-BORNE DISEASES. EXPOSURE IN RURAL AREAS OFTEN CAN BE AVOIDED BY SITING BIVOUAC AREAS WELL AWAY FROM RODENT BURROWS, SINCE SAND FLIES FLY ONLY AT NIGHT AND RARELY MORE THAN 100 METERS FROM THEIR RODENT BURROW HABITATS. IF SAND FLY INFESTED AREAS CANNOT BE AVOIDED, RECOMMENDED MEASURES USUALLY INCLUDE USE OF PERSONAL REPELLENTS (DEET), VECTOR CONTROL OPERATIONS, OR THE DESTRUCTION OF VECTOR HABITATS (RODENT BURROWS). VACCINES AND CHEMOPROPHYLAXIS ARE NOT AVAILABLE FOR U.S. PERSONNEL FOR THESE DISEASES. [b.6.] BT
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