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Outbreaks, Alerts and Hot Topics

May 2019

Spring and Summer Infections


Mary Anne Jackson, MD | Interim Dean - UMKC School of Medicine | Medical Editor, The Link Newsletter 

The end of influenza season is finally here and 2018-2019 will go on record as the longest flu season in the last decade. Two strains circulated widely, with influenza A H1N1 predominating from October into February. A second wave with influenza A H3N2 began in February and persisted into April. Influenza B appeared early in October, but smaller than expected numbers have been seen overall.

While the number of children presenting with nonspecific febrile illness may decrease compared to the winter months, a wide array of pathogens will circulate in spring and summer causing febrile illnesses. Recognition of the distinct clinical presentations among the infections that tend to predominate in spring and summer should allow timely diagnosis and treatment.

1. Hand, foot and mouth disease (HFMD) and herpangina
2. Ehrlichiosis and spotted fever rickettsiosis
3. Water-borne diarrheal pathogens
4. Other viral infections-roseola, enteroviral or parechovirus meningitis

Features of Spring and Summer Infections










Coxsackie A16

Less than 5 years

Childcare, sibling positive

Fever, vesicles in mouth, palms, soles



Resolution of lesions in 7-10 days


Coxsackie A viruses



Posterior pharynx vesicles



Resolution in 2-4 days

Eczema coxsackium

Coxsackie A6

All ages including adults; usually infants

Family outbreaks described

Perioral, trunk, buttocks widespread painful, pruritic, papulovesicular; may cluster in areas of eczema, trauma

Clinical, may mimic eczema herpeticum; rare Gianotti-Crosti lesions, or purpuric lesions (>5 years)


Resolution 10-14 days

Beau’s lines on finger- toe-nails and onychomadesis, or desquamation can occur weeks after diagnosis

Ehrlichiosis and spotted fever rickettsiosis

Ehrlichia chafeensis; Rickettsia rickettsiae

All ages, highest mortality <5 years

Tick exposure

Fever, headache, myalgia, distal rash

Clinical; leukopenia, thrombocytopenia, transaminitis, hyponatremia may be clues; antibody testing not helpful early on

Doxycycline for all ages-initiate promptly 

RMSF, death if diagnosis delayed beyond day 5


Cryptosporidia parvum

Young children

Recreational water exposure; childcare; symptomatic contact

Watery diarrhea may be profuse

Stool PCR or EIA


Resolution 2-3 weeks without treatment in immune competent; 5-7 days with treatment

Viral meningitis

Echoviruses, coxsackie viruses, other enteroviruses, parechovirus (PeV); EV types vary year to year

Infants; young children

Occasionally outbreaks

Fever, headache, irritability, meningismus;

Infant PeV presents as sepsis like illness.

CSF lymphocytic pleocytosis; differentiate from HSV CNS infection. CSF enterovirus, PeV and HSV PCR. CSF WBC absent with PEV

Self-limited; initiate acyclovir if HSV encephalitis suspected

EV and PeV resolve in 2-4 days; HSV can be devastating without prompt treatment



<2 years

Child care

High fever for 3-5 days; blanching maculopapules as defervescence occurs



Febrile seizures in 15%

Of the more than 100 enteroviruses that are described, the Coxsackie viruses, some of the numbered enteroviruses (e.g., EV-D68) and echoviruses most often circulate from May into early autumn. Coxsackie A16 is the cause of most cases of HFMD, though outbreaks caused by Coxsackie A-6, -8, -10 and -22 are also reported. Infection is most commonly seen in children less than 5 years of age who present with fever, followed by the typical enathem and localized skin lesions that appear on the palms, soles and sometimes the buttocks. Herpangina presents with fever and painful vesicles/ulcers predominating in the posterior oropharynx or palate, and is also caused most commonly by Coxsackie A serotypes. Diagnostic testing in most cases of HFMD or herpangina is not necessary as disease is self-limited and lesions resolve generally within 7-10 days.

Atypical presentations of HFMD have been associated with Coxsackie A6 infections and lesions may be papulovesicular and tend to cluster on the buttocks, trunk and perioral area.1 Some lesions may be large and appear vesicobullous in nature. In individuals with eczema, lesions may appear in areas of eczematous skin and have led to the term “eczema coxsackium” as the lesions may mimic eczema herpeticum (EH) or even staphylococcal superinfection. In such cases, diagnostic testing, including bacterial and HSV cultures or HSV PCR, should be considered if empiric use of acyclovir for EH or antibiotics directed toward Staphylococcus aureus are planned.

Most patients presenting with tick-borne disease initially have flu-like symptoms including fever, chills, headache and myalgia. Gastrointestinal symptoms may also be present and Rocky Mountain Spotted Fever (RMSF) should be included in the differential for community-acquired pneumonia. Rash is more often present in RMSF than ehrlichiosis, but does not appear until day 2-4 of infection. Macules appear first on the wrists and ankles, and may become petechial (best seen on the palms and soles). While the distinctive rash of tick-borne infection may suggest the diagnosis, recognize that rash may be absent in 10-15% of RMSF patients (and >80% of ehrlichia patients). Disease incidence increases with increasing age overall, but children are more likely to die from RMSF. History of tick exposure should be sought, but is negative in 30-50% and the triad of fever, tick exposure and rash is only present in one-third of cases.2 Laboratory studies which may suggest the diagnosis include leukopenia, thrombocytopenia, liver transaminitis and hyponatremia, but normal laboratory values cannot be used to exclude the diagnosis. Treatment should be initiated, as soon as tick-borne disease is suspected. Death rates from RMSF increase if the diagnosis is delayed beyond day 5.2 Doxycycline is the drug of choice for ehrlichiosis and RMSF, and is indicated for all ages. Parents may be told that single courses of doxycycline will not cause tooth staining or changes in enamel.3

Cryptosporidiosis should be suspected in young children who present with profuse watery diarrhea. Exposure to recreational water (pools and interactive water foundations), contaminated drinking water (camping) or contact with other infected individuals (diapered children in childcare) can be a clue to diagnosis.4 Diarrheal symptoms may be prolonged in cryptosporidiosis, but diarrhea usually resolves in immunocompetent hosts in 2-3 weeks. Nitazoxanide is licensed for all ≥1 year of age and produces clinical cure in up to 88% and parasitic cure in 60-75%. Up to 108 oocysts may be shed in stool and remain infectious for up to 60 days after diarrhea has resolved, supporting the recommendation that infected individuals not swim for 2 weeks after symptom resolution.

Other viral infections clinicians may encounter in the spring and summer include adenovirus or enteroviruses, respiratory illnesses and conjunctivitis. Enteroviral meningitis season usually begins in late spring, often in June, peaking in August-September and ending in fall. Young infants with sepsis-like presentations may actually have Parechovirus-3 (PeV-3), which often infects the CNS, but does not cause pleocytosis. Diagnosis is by CSF PCR. Roseola is typically caused by HHV-6B strains in infants under age 2 years. They present with high fever up to 40C for 3-5 days before rapid defervescence. With resolution of fever comes blanching, and nonpruritic truncal macules or papules that may have a surrounding halo appearance and can spread to the neck, extremities and face. Febrile seizures may be seen in up to 15% of HHV6-infected children.


1. Hand, Foot, and Mouth Disease Caused by Coxsackievirus A6. Flett K, Youngster I, Huang J, McAdam A, Sandora TJ, Rennick M, et al. Emerg Infect Dis. 2012;18(10):1702-1704.

2. Risk Factors for Fatal Outcome from Rocky Mountain Spotted Fever in a Highly Endemic Area-Arizona, 2002-2011. Regan JJ, Traeger MS, Humpherys D, et al. Clin Infect Dis. 2015;60(11):1659–1666. doi:10.1093/cid/civ116.

3. No Visible Dental Staining in Children Treated with Doxycycline for Suspected Rocky Mountain Spotted Fever. Todd SR, Dahlgren FS, Traeger MS, et al. J Pediatr. 2015 May;166(5):1246-51. doi: 10.1016/j.jpeds.2015.02.015.

4. Cryptosporidiosis Surveillance-United States, 2009-2010. Yoder JS, Wallace RM, Collier SA, et al. MMWR. Sept 7, 2012;61(SS05);1-12.