Most people have never heard of murine typhus. Doctors in Galveston, Texas, are asking them to pay attention.
A study published in the CDC's Emerging Infectious Diseases journal, Volume 32, Number 6 (June 2026) by researchers at the University of Texas Medical Branch (UTMB) in Galveston analyzed five years of murine typhus cases and found a disease that is sicker and more dangerous than many clinicians expect. Lead author Matthew Pickich and colleagues — Puneet Singh, Efstathia Polychronopoulou, Shawn P. Nishi, Lucas S. Blanton, and Alexander G. Duarte — examined 149 confirmed and probable murine typhus cases in Galveston from 2019 to 2023.
Of those 149 cases, 119 (79.8%) required hospitalization — already a striking figure for what many physicians consider a manageable febrile illness. Of the hospitalized patients, 33 (28%) required admission to the intensive care unit. Two patients died. Both deaths were attributed to multiorgan failure and hemophagocytic lymphohistiocytosis (HLH) — a life-threatening immune dysregulation syndrome.
The study identified key risk factors for ICU admission: ICU patients were significantly older than non-ICU patients (median age 54.9 years vs. 47.2 years; p<0.02), and they experienced more severe drops in platelet counts — thrombocytopenia at 101 × 10³ µ/L in ICU patients versus 137 × 10³ µ/L in non-ICU patients (p<0.01). "In murine typhus–endemic regions, early recognition and prompt treatment is imperative to mitigate adverse outcomes," the study concluded.
| Galveston Murine Typhus Study Data (2019–2023) | Detail |
| Total confirmed and probable cases | 149 |
| Hospitalized | 119 (79.8%) |
| Required ICU admission | 33 (28% of hospitalized) |
| Deaths | 2 (1.7% of ICU patients) |
| Cause of deaths | Multiorgan failure and HLH |
| ICU median age | 54.9 years |
| Non-ICU median age | 47.2 years |
| ICU platelet count (median) | 101 × 10³ µ/L |
| Non-ICU platelet count (median) | 137 × 10³ µ/L |
| Published in | CDC EID Journal, June 2026 |
A Disease Resurging After Decades of Near-Eradication
Murine typhus, also known as endemic or flea-borne typhus, is caused by Rickettsia typhi, an obligately intracellular bacterium. Once prevalent across the United States, the disease was nearly eliminated in the 1940s following vector control campaigns using DDT that decimated rat flea populations. In Galveston, the disease was essentially absent for decades. Its return is documented in a disturbing progression.
A 2023 EID study — which preceded the 2026 study — conducted a serosurvey of Galveston County residents and found that antibody evidence of Rickettsia typhi infection increased from 1.2% of the population in 2013 to 7.8% in 2021, a statistically significant jump that the study's authors concluded "support pathogen reemergence rather than enhanced recognition alone." In other words, more people are genuinely being infected — not just more cases being caught by better testing.
An earlier 2020 EID study documented 40 cases in Galveston County in a single year (2018) — "unprecedented since the 1940s." The contemporary transmission cycle no longer involves the classic urban rat-rat-flea pathway. In modern Galveston, the disease is primarily transmitted through Virginia opossums and cat fleas (Ctenocephalides felis) — a suburban and peri-urban cycle that can bring the disease directly into yards, parking areas, and even homes where feral cats or wildlife are present.
Who Is at Risk and What to Watch For — Houston, Galveston, and South Texas Residents
The UTMB study's finding that 79.8% of murine typhus patients required hospitalization — and nearly one in three required ICU care — is a clear signal that this disease is being severely underestimated in clinical settings. Because murine typhus presents initially as an undifferentiated febrile illness that looks almost identical to the flu, COVID-19, dengue, or other febrile syndromes, it is frequently misdiagnosed or not tested for, which delays life-saving antibiotic treatment.
Murine typhus symptoms typically develop 6 to 14 days after a flea bite and include: sudden high fever (typically above 101.5°F), severe headache, chills, myalgia (muscle aches), anorexia, nausea, and vomiting. A rash — typically beginning on the trunk and spreading outward — appears in approximately 50 to 80% of patients, usually within the first few days of fever onset. The rash is often subtle and may be missed, particularly in patients with darker skin tones.
The antibiotic of choice for murine typhus is doxycycline, which must be started promptly. The UTMB study found that the median time from emergency department contact to appropriate antibiotic initiation was approximately one day for ICU patients and two days for non-ICU patients — a narrow but significant window in which the disease can advance. "Early recognition and prompt treatment is imperative," the study's authors state directly.
High-risk activities include contact with feral cats or opossums, spending time in areas where these animals roam (including suburban yards, outdoor restaurants, and parking lots), and any exposure to fleas. Galveston County, Harris County (Houston), and other Gulf Coast Texas counties are the highest-risk areas within the United States. Residents who develop fever and headache within two weeks of potential flea exposure should specifically ask their physician about testing for murine typhus, as the diagnosis requires suspicion-based testing that is frequently not ordered on first presentation.
Frequently Asked Questions
What is murine typhus, and how is it spread?
Murine typhus is a flea-borne bacterial disease caused by Rickettsia typhi. It is transmitted to humans through flea feces contaminating skin wounds or mucous membranes, or through direct flea bites. In modern Texas, the primary transmission cycle involves Virginia opossums and cat fleas, making suburban and residential exposures increasingly common.
How many people got sick from murine typhus in Galveston from 2019 to 2023?
The UTMB study in CDC's EID journal identified 149 confirmed and probable murine typhus cases. Of those, 119 (79.8%) were hospitalized, and 33 (28% of hospitalized patients) required ICU care. Two patients died from multiorgan failure.
What are the symptoms of murine typhus?
Murine typhus begins 6 to 14 days after flea exposure with sudden high fever, severe headache, chills, muscle aches, anorexia, nausea, and vomiting. A rash appears in about half to two-thirds of patients, typically starting on the trunk. The illness is often initially mistaken for flu, COVID-19, or dengue.
Who is at highest risk?
The UTMB study found that ICU patients were significantly older than non-ICU patients, with a median age of nearly 55 years. Older adults are at highest risk of severe disease. People in Galveston County, Harris County, and other Gulf Coast Texas areas who have contact with feral cats, opossums, or areas where these animals are present face the highest exposure risk.
How is murine typhus treated?
The treatment of choice is doxycycline, which should be started as early as possible. Delays in diagnosis, which are common because murine typhus mimics other febrile illnesses, are a key driver of severe outcomes. Anyone in a high-risk area who develops fever and headache within two weeks of possible flea exposure should ask specifically about murine typhus testing.
