MICROBIOLOGY AND EPIDEMIOLOGY OF INFECTIOUS DISEASES IN DOD BENeficiaries 

THE PROBLEM

Multidrug-resistant organisms(MDRO) are a major public health threat in the United States and around the globe. The U.S. military considers these pathogens to be a major threat to military readiness and MDRO research to be a priority area of investigation. The microbiology of many common pediatric infections has also changed in the modern vaccine era. The rise of resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), extended spectrum beta-lactamase (ESBL) producing gram-negative bacilli, and carbapenem-resistant Enterobacteriaceae (CRE), has made initial antimicrobial decision-making challenging. Updated evaluations of microbiologic and epidemiologic data are therefore needed to inform optimal empiric antimicrobial management for many infections in children and adults. 

OUR APPROACH

The objective of our research is to evaluate the modern microbiology and epidemiologic exposures associated with infections in DoD beneficiaries, both children and adults.

Previous military health system database information has also been used to research certain viral infections in the DoD, particularly Respiratory Syncytial virus (RSV) bronchiolitis and Rotavirus gastroenteritis. These epidemiologic studies have led to publications that identified risk for factors for severe RSV disease and vaccine effectiveness data on the rotavirus vaccine. In addition, the databases were used to explore the rising number of Clostridium difficile infections (CDI) in patient populations. Clostridium difficile infections are now estimated to occur in over half a million Americans a year, making it the most common bacterial enteritis. CDI were known to be associated with antibiotic administration in adults. However beyond this, almost nothing was known about the epidemiology of CDI in children.

RESULTS & ADVANCEMENTS

Our group published the first major article reporting the increasing trend of CDI in children in the US and reported that CDI is associated with increased risk of colectomy and death in children.1 We have also identified an increased risk for CDI in children who are prescribed certain classes of medications such as proton pump inhibitors, histamine-2 receptor antagonists, corticosteroids, and specific classes of antibiotics.2-3 The publication resulting from this research demonstrated that with each additional class of antibiotic a child is exposed to, their risk doubles for CDI.3 CDI was traditionally thought to occur only in hospitalized children, however, we identified an increasing trend in community associated CDI in children.3 

 

The COVID pandemic caused a significant and lasting disruptive impact on healthcare delivery and routine immunization. Our division recently used the MDR to explore and characterize the COVID pandemic impact on congenital syphilis care, RSV seasonality, vaccine preventable infections such as rotavirus, S. pneumoniae, and H. influenzae, and vaccine delivery to pediatric and adolescent populations.4-6 Additionally we recently published an updated microbiology of orbital cellulitis in the US Military Health System.7 These data are critically important to improving understanding of well-established, novel, and re-emerging infections, and to informing optimal empiric antibiotic treatment and prevention of these infections in pediatric and adult populations.

 

NOTABLE PUBLICATIONS

  1. Nylund CM, Goudie A, Garza JM, Fairbrother G, Cohen MB. Clostridium difficile infection in hospitalized children in the United States. Arch Pediatr Adolesc Med. 2011 May;165(5):451-7. doi: 10.1001/archpediatrics.2010.282. Epub 2011 Jan 3. PMID: 21199971; PMCID: PMC4683604.
  2. Nylund CM, Eide M, Gorman GH. Association of Clostridium difficile infections with acid suppression medications in children. J Pediatr. 2014 Nov;165(5):979-84.e1. doi: 10.1016/j.jpeds.2014.06.062. Epub 2014 Aug 8. PMID: 25112692.
  3. Adams DJ, Eberly MD, Rajnik M, Nylund CM. Risk Factors for Community-Associated Clostridium difficile Infection in Children. J Pediatr. 2017 Jul;186:105-109. doi: 10.1016/j.jpeds.2017.03.032. Epub 2017 Apr 7. PMID: 28396027.
  4. Teng J, Prabhakar S, Rajnik M (Ret), Susi A, Hisle-Gorman E, Nylund CM, Brown J (Ret). Impact of the COVID-19 Pandemic on the Delivery of Congenital Syphilis Care in the Military Health System. Mil Med. 2024 Aug 14:usae392. doi: 10.1093/milmed/usae392. Epub ahead of print. PMID: 39141422.
  5. Zven S, Dorr M, Malloy AMW, Susi A, Nylund CM, Hisle-Gorman E. Predicting the RSV Surge: Pediatric RSV Patterns of the COVID Pandemic. Pediatr Infect Dis J. 2023 Sep 1;42(9):e349-e351. doi: 10.1097/INF.0000000000003980. Epub 2023 May 24. PMID: 37235765; PMCID: PMC10627385.
  6. Sexton K, Susi A, Lee E, Hisle-Gorman E, Rajnik M, Krishnamurthy J, Nylund CM. Trends in Well-Child Visits and Routine Vaccination among Children of U.S. Military Members: An Evaluation of the COVID-19 Pandemic Effects. J Clin Med. 2022 Nov 19;11(22):6842. doi: 10.3390/jcm11226842. PMID: 36431319; PMCID: PMC9699213.
  7. Cirks BT, Claunch KM, DePerrior S, Poitras B, Adams DJ. Microbiology and Epidemiology of Orbital Cellulitis in Pediatric and Young Adult Patients. Mil Med. 2024 Aug 22:usae394. doi: 10.1093/milmed/usae394. Epub ahead of print. PMID: 39172646.