MSMR最新文献

Adenovirus outbreaks have long been a cause of acute respiratory disease, hospitalization, and death in otherwise young, healthy military recruits. The administration of oral, live attenuated adenovirus (AdV) vaccine against AdV types 4 and 7 has been critical in preventing outbreaks in this population.1-4 In early July 2024, a spike in recruit hospitalizations for AdV pneumonia was recognized at the Marine Corps Recruit Depot (MCRD) San Diego, and an outbreak investigation commenced. From July 1 through September 23, 2024, a total of 212 AdV cases, including 28 hospitalizations, were identified among trainees and staff. Non-pharmaceutical interventions, including aggressive environmental cleaning, separation of sick and well recruits, and masking, were implemented. The outbreak was not appreciably slowed, however, until AdV vaccine administration was advanced from day 11 to day 1 post-arrival of recruits to MCRD San Diego. This outbreak report demonstrates that early AdV vaccination for newly arriving recruits is an effective and essential step in preventing AdV morbidity and mortality in a recruit training setting. Despite the availability and widespread use of effective vaccines during recruit training, adenovirus outbreaks remain a significant threat to military recruits if the vaccine is not administered expediently, upon arrival to the recruit training center.

In 2024, the crude incidence rates of heat stroke and heat exhaustion were 36.4 and 183.9 cases per 100,000 person-years, respectively. After a period of decline in rates of incident heat stroke from 2020 through 2023, during the 2024 surveillance period an increase was observed. When considering only heat exhaustion, incident rates increased each year during the 5-year surveillance period, from 2020 through 2024. In 2024, higher rates of heat stroke were observed among male service members, when compared to their female counterparts, as well as among non-Hispanic White service members compared to service members of other races and ethnicities. Female service members and non-Hispanic Black service members experienced higher rates of heat exhaustion than their male counterparts and service members of other races and ethnicities, respectively. Heat illness rates were also higher among those younger than age 20 years, Marine Corps and Army service members, and recruit trainees. To mitigate the personal and organizational impacts of heat illness, leaders, training cadres, and supporting medical and safety personnel must inform both their subordinate and supported service members of heat illness risks, preventive measures, early signs and symptoms of illness, and appropriate interventions. In 2024, the crude annual incidence rate of heat stroke increased 16.5%, following a 4-year decrease of 10.8% from 2020 to 2023. All services, apart from the Space Force and Coast Guard, had a higher rate of heat stroke in 2024 than in 2023. The crude annual incidence rate of heat exhaustion increased 52.3% from 2020 to 2024, with incremental increases annually. Increased rates of heat exhaustion in 2024 from 2023 were observed in the Army, Marine Corps, and Coast Guard.

Exertional hyponatremia, or hyponatremia associated with exercise, occurs within 24 hours after physical activity due to a serum, plasma, or blood sodium concentration ([Na+]) below the normal reference range of 135 mEq/L. Hyponatremia can be fatal if not detected early and managed properly. From 2009 to 2024, 1,829 cases of exertional hyponatremia were diagnosed among U.S. active component service members (ACSMs), with an overall incidence rate of 8.4 cases per 100,000 person-years (p-yrs). In 2024, 134 cases of exertional hyponatremia were diagnosed among ACSMs, resulting in a crude incidence rate of 10.4 per 100,000 p-yrs. Female service members, those older than 40 years, non-Hispanic White service members, Marine Corps members, recruits, those in health care occupations, and ACSMs stationed in the Midwest U.S. had higher incidence rates of diagnosis for exertional hyponatremia than their respective counterparts. From 2009 to 2024, annual rates of incident exertional hyponatremia diagnoses peaked in 2010 (12.8 per 100,000 p-yrs) and then decreased to a low of 5.3 cases per 100,000 p-yrs in 2013. The incidence rate has fluctuated since then, rising from 6.1 per 100,000 p-yrs in 2017 to the second-highest level (11.2 per 100,000 p-yrs) in 2023 before decreasing to 10.4 per 100,000 p-yrs in 2024. Service members and their supervisors must be aware of the dangers of excessive consumption of water and the prescribed limits of water intake during prolonged physical activity, including field training exercises, personal fitness training, as well as recreational activities, particularly in hot, humid weather. Incidence rates of exertional hyponatremia changed from 2023 to 2024, with the overall incidence rate decreasing from 11.2 to 10.4 per 100,000 p-yrs. Rates increased, however, in the 25-29 years age group and in the Coast Guard, while decreasing sharply among non-Hispanic Black individuals and recruits. The highest incidence rates were observed in non-Hispanic White individuals and health care personnel.

Exertional rhabdomyolysis is a pathologic muscle breakdown associated with strenuous physical activity. A largely preventable condition, it persists as an occupational hazard of military training and operations, especially in high heat environments among individuals pushing their endurance limits. A total of 464 cases of exertional rhabdomyolysis were identified in 2024, corresponding to a crude incidence rate of 35.9 cases per 100,000 person-years, and is the lowest case count recorded during the 2020-2024 period of surveillance. The 2024 case numbers demonstrated a 9.6% reduction from the peak rate in 2023, and the proportion of 39.7% hospitalized in 2024 represented a 4.0% decrease from 2023. In 2024, all services, excepting the Navy, showed declines in incidence rates, ranging from 2.0% in the Coast Guard to 29.1% in the Air Force, compared to 2023. Consistent with prior reports, subgroup-specific crude rates in 2024 were highest among men, those less than 20 years old, non-Hispanic Black service members, Marine Corps or Army members, and those in combat-specific or 'other' military occupations. Recruit trainees continued to experience the highest rates of exertional rhabdomyolysis in 2024, with a rate more than 13 times greater than officers and enlisted members. During the 2020-2024 surveillance period, 2024 evinced the lowest incidence rate of exertional rhabdomyolysis, nearly 10% lower than the peak observed in 2023. The Air Force showed the largest reduction, with incidence rates decreasing approximately 30% from the previous year.

Studies of sepsis within the U.S. military population have consistently shown that rates of sepsis have increased over time. The observed higher incidence of sepsis in studies among women compared to men of the active component U.S. military population is of concern and warrants further evaluation, as it diverges from incidence typically observed in the U.S. general population. The objectives of this study were to examine cases of sepsis among active component U.S. service women between January 1, 2011 and December 31, 2022, compare them to active component men in the U.S. military, and identify factors associated with sepsis among female active component service members. In this study, female active component service members evinced higher rates (66.5 per 100,000 person-years) compared to males (36.7 per 100,000 person-years), with a rate of sepsis 1.9 times higher after adjusting for demographic and military-related factors. Rates of sepsis were higher among women with a history of co-morbidities. Rates of sepsis hospitalizations among female active component service members have consistently been higher compared to male active component members. Female active component members had 1.9 times higher rates for hospitalization for sepsis compared to active component service men after adjusting for demographic and military-related factors.