INFECTIOUS DISEASES - Blackherbals.com

Chik Virus Has NowSpread To the USFrom The CDCSeptember 29, 2006Chikungunya Fever Diagnosed Among InternationalTravelers -- United States, 2005 --2006Chikungunya virus (CHIKV) is an alphavirusindigenous to tropical Africa and Asia, where it istransmitted to humans by the bite of infectedmosquitoes, usually of the genus Aedes (1).Chikungunya (CHIK) fever, the disease caused byCHIKV, was first recognized in epidemic form inEast Africa during 1952-1953. The word"chikungunya" is thought to derive from descriptionin local dialect of the contorted posture of patientsafflicted with the severe joint pain associated withthis disease. Because CHIK fever epidemics aresustained by human-mosquito-humantransmission, the epidemic cycle is similar to those ofdengue and urban yellow fever. Large outbreaks ofCHIK fever have been reported recently on severalislands in the Indian Ocean and in India (refs. 2-6). In2006, CHIK fever cases also have been reported intravelers returning from known outbreak areas toEurope, Canada, the Caribbean (Martinique), andSouth America (French Guyana) (2,3,5-7). During2005-2006, 12 cases of CHIK fever were diagnosedserologically and virologically at CDC in travelerswho arrived in the United States from areas known tobe epidemic or endemic for CHIK fever. This reportdescribes 4 of these cases and provides guidance tohealth-care providers.Clinicians should be alert for additional cases amongtravelers, and public health officials should be alert toevidence of local transmission of chikungunya virus(CHIKV), introduced through infection of localmosquitoes by a person with viremia.Case Reports ------ Minnesota. On 12 May 2005, anadult male resident of Minnesota returned from a 3-month trip to Somalia and Kenya. He had onset ofillness hours after arrival in the United States,including fever, headache, malaise, and joint painmainly in a shoulder and a kneeLouisiana. On 15 Jan 2006, an adult female residentof India had onset of an illness characterized byfever, joint pain (in the knees, wrists, hands, andfeet), and muscle pain (in the thighs and neck). InMarch 2006, she traveled to Louisiana, where she soughtmedical attention for persistent joint pain. At CDC, testsof a single serum sample collected on 30 Mar [2006] (74days after illness onset) were positive for IgM andneutralizing antibodies to CHIKV. The patient wassubsequently lost to follow-up.Maryland. An adult female resident of Maryland visitedthe island of Reunion in the Indian Ocean from October2005 through mid-March 2006. On 18 Feb 2006, duringan ongoing CHIK fever outbreak on the island, she hadonset of fever, joint pain (in the hands and feet), and rash.A local physician clinically diagnosed CHIK fever, butno laboratory tests were conducted. After returning to theUnited States, the patient sought medical attention forpersistent joint pain. At CDC, tests of a single serumsample collected on 22 Mar [2006](32 days after illnessonset) were equivocal for IgM and positive forneutralizing antibody to CHIKV, consistent with a recentCHIKV infection in which IgM antibody was waning. At5 months after onset, the patient had persistent joint pain(in the hands and feet).Colorado. An adult male resident of Colorado visitedZimbabwe during 17 Apr -- 29 May 2006. On 29 Apr[2006], he had onset of illness with fever, chills, jointpain (in the wrists and ankles), and neck stiffness; a rashappeared a few days later. All symptoms resolved within2 weeks, except for joint pain, which persisted forapproximately 1 month. At CDC, tests of a single serumsample collected on 12 Jun [2006] (44 days after illnessonset) were positive for IgM and neutralizing antibody toCHIKV.MMWR Editorial Note:Most CHIKV infections are symptomatic (8). In clinicalinfections, the incubation period typically is 2-4 days.Illness is characterized by sudden onset of fever,headache, malaise, arthralgias or arthritis, myalgias, andlow back pain. Skin rash occurs in approximately half ofcases (9). Joint symptoms can be severe and involvesmall and large joints. Although CHIK fever typicallylasts 3-7 days and full recovery is the usual outcome,certain patients experience persistent joint symptoms forweeks or months and occasionally years after illnessonset (1).Serious complications (e.g., neuroinvasive disease) arerare, and fatal cases have not been documentedconclusively. Transplacental CHIKV transmission andsevere congenital CHIKV disease have been described(10). CHIKV infection is believed to confer life-longimmunity (1).Because no specific drug therapy is available, treatmentContinued on page 25-24- Traditional African Clinic December 2006