Pediatric Lyme Disease Seasonality in Endemic Regions

A study examining pediatric Lyme disease seasonality found that most children in endemic regions present during the summer months. However, the findings also raise questions about how Lyme disease is diagnosed in children and how many cases may be overlooked.

The study’s objective

was to evaluate the seasonality of pediatric Lyme disease across three endemic regions of the United States, according to Sundheim and colleagues. Participants were treated at eight medical centers located throughout the Northeast and Upper Midwest—regions where Lyme disease is common.

Among the 690 children diagnosed with Lyme disease:

• 77 children (11.2%) had a single erythema migrans (EM) lesion
• 247 children (35.7%) had early disseminated disease
• 366 children (53.1%) presented with Lyme arthritis

The authors reported that children with early and early-disseminated Lyme disease most frequently presented during the summer months (June through August).

Because all participating centers were located in Lyme-endemic regions, the authors noted that the findings may not apply to areas of the United States where Lyme disease is less common.

Co-infections Not Routinely Evaluated

The investigators did not routinely test for tick-borne co-infections. However, previous studies using multiplex polymerase chain reaction (PCR) panels have shown that a substantial portion of adults with Lyme disease may also have additional tick-borne infections.

Editor’s Comments

Sundheim and colleagues classified 2,490 children (78.3%) as clinical mimics rather than confirmed Lyme disease cases.

It would have been valuable if the investigators had followed these children over time to determine whether some later developed Lyme disease or other tick-borne illnesses.

The study also focused primarily on three clinical presentations of Lyme disease:

• Early disease (single erythema migrans lesion)
• Early disseminated disease (multiple EM lesions, headache, cranial neuropathy, or carditis)
• Late disease (Lyme arthritis)

Other possible manifestations of Lyme disease were not examined in this analysis, which may limit how broadly the results can be interpreted.

Dr. Daniel Cameron, MD, MPH
Lyme disease clinician with over 30 years of experience and past president of ILADS.

Symptoms • Testing • Coinfections • Recovery • Pediatric • Prevention