Trends in varicella mortality in the United States: Data from vital statistics and the national surveillance system

Figures & data

Table 1. Annual Varicella-Related Deaths in the United States, According to Underlying or Contributing Cause, National Vital Statistics System Data, 1990–2011

	Varicella listed as underlying cause of death			Varicella listed as contributing cause of death
	1990–1994^a	2005–2007^b	2008–2011^c	1990–1994^a	2005–2007^b	2008–2011
Total average no. of deaths per year	105	15	17	39.6	20.3	16.3
Average no. (%) of deaths per year
Age group (years)
<1	8.8 (8.4)	0 (0.0)	0.0 (0.0)	3 (7.6)	0.0 (0.0)	0.0 (0.0)
1–4	13.2 (12.6)	0.7 (4.4)	0.0 (0.0)	5.2 (13.4)	0.7 (3.3)	0.5 (3.1)
5–9	15.6 (14.9)	0.3 (2.2)	0.0 (0.0)	3.2 (8.1)	0.0 (0.0)	0.0 (0.0)
10–19	10.4 (9.9)	0.7 (4.4)	0.5 (2.9)	2.2 (5.6)	0.3 (1.6)	0.3 (1.5)
20–49	35.6 (33.9)	3.3 (22.2)	4.5 (26.1)	11.6 (29.3)	3.0 (14.8)	2.0 (12.3)
≥50	21.4 (20.4)	10.0 (66.7)	12.3 (71.0)	14.4 (15.3)	15.3 (80.3)	13.5 (83.1)
Gender
Male	55.4 (52.8)	8.7 (57.8)	9.8 (56.5)	24.8 (62.6)	11.3 (55.7)	9.3 (56.9)
Female	49.6 (47.2)	6.3 (42.2)	7.5 (43.5)	14.8 (37.4)	9.0 (44.3)	7.0 (43.1)
Race
White	78.6 (74.9)	13.7 (91.1)	15.0 (87.0)	28.8 (72.7)	17.3 (85.3)	14.0 (86.2)
Black	19.2 (18.3)	0.7 (4.4)	0.8 (4.3)	8.8 (22.2)	2.0 (9.8)	1.0 (6.2)
Other	7.2 (6.9)	0.7 (4.4)	1.5 (8.7)	2.0 (5.1)	1.0 (4.9)	1.3 (7.7)
Ethnicity
Non-Hispanic	87.6 (83.4)	12.3 (82.2)	14.8 (85.5)	34.2 (86.4)	19.7 (96.7)	14.0 (86.2)
Hispanic	14.8 (14.1)	2.7 (17.8)	2.3 (13.0)	4.4 (11.1)	0.7 (3.3)	2.3 (13.8)

^aData are from Meyer et al.²

^bData are from Marin et al.⁴

^cData on deaths with varicella listed as the underlying cause by year included in Supplementary Table 1.

Table 2. Demographic Characteristics of Varicella Deaths, National Varicella Death Surveillance Data, United States, 1996–2013

	Varicella Death Classification
Variable	Likely Varicella-Related Death N=83 No. (%)	Unlikely Varicella-Related Death or Unknown^a N=13 No. (%)
# States reporting	28 states	9 states
Period
1996–2001	39 (47)	4 (31)
2002–2006	22 (27)	3 (23)
2007–2013	22 (27)	6 (46)
Age group (years)
< 1	3 (4)	0 (0)
1–9	23 (28)	2 (15)
10–19	11 (13)	1 (8)
20–49	41 (49)	2 (15)
≥50	5 (6)	8 (62)
Gender
Male	43 (52)	11 (85)
Female	40 (48)	2 (15)
Race
African American	13 (16)	1 (8)
White	56 (67)	10 (77)
Other	9 (11)	2 (15)
Unknown	5 (6)	0 (0)
Ethnicity
Hispanic	23 (28)	1 (8)
Non-Hispanic	48 (58)	8 (67)
Unknown	11 (13)	3 (25)
Country of birth
United States	56 (67)	7 (18)
Foreign-born^b	18 (22)	4 (10)
Unknown	9 (11)	2 (5)

^a7 varicella deaths classified as unknown.

^bAmong 18 varicella deaths in foreign-born persons classified as likely varicella-related, 9 were from S. America, 3 from Asia, 2 from Europe, 2 from Africa, and 2 from US territories. Among 4 varicella deaths in foreign-born persons classified as unlikely varicella-related or unknown, 2 were from Europe, 1 from S. America, and 1 from Asia.

Table 3. Characteristics of Varicella Deaths by Age Group, National Varicella Death Surveillance Data, United States, 1996–2013

	Age Group (Years)		≥20 Year-Olds N=46
Variable	0–9 Year-Olds N=26 No. (%)	10–19 Year-Olds N=11 No. (%)	No. (%)
History of prior varicella disease
Yes	0 (0)	2 (18)	3 (7)
No	25 (96)	7 (64)	26 (57)
Unknown	1 (4)	2 (18)	17 (37)
Varicella vaccination
Yes	4 (15)	1 (9)	0 (0)
No	20 (77)	10 (91)	28 (61)
Unknown	2 (8)	0 (0)	18 (39)
Immunocompromised
Yes	6 (23)	2 (18)	16 (35)
HIV/AIDS	0 (0)	0 (0)	2 (4)
Cancer	3 (12)	1 (9)	2 (4)
Immunodeficiency	1 (4)	0 (0)	3 (7)
Immunosuppressive treatment only	2 (8)	1 (9)	9 (20)
No	18 (69)	7 (64)	28 (61)
Unknown^a	2 (8)	2 (18)	2 (4)
Complications^b
Yes	26 (100)	11 (100)	45 (98)
No	0 (0)	0 (0)	1 (2)
Laboratory-confirmed varicella zoster virus infection^c
Yes	11 (42)	8 (73)	31 (67)
No	15 (58)	3 (27)	15 (33)
Autopsy
Yes	18 (69)	5 (45)	21 (46)
If yes, pathological evidence of varicella-zoster virus infection	13 (72)	2 (40)	17 (81)
No	8 (31)	6 (55)	25 (54)
Transmission source
Varicella	10 (38)	5 (45)	21 (46)
Herpes zoster	1 (4)	0 (0)	2 (4)
Unknown or missing	15 (58)	6 (55)	23 (50)
Transmission setting
Home	7 (27)	0 (0)	19 (41)
School	3 (12)	5 (45)	0 (0)
College	0 (0)	0 (0)	1 (2)
Hospital	0 (0)	0 (0)	1 (2)
Other	1 (4)	0 (0)	2 (4)
Unknown or missing	15 (58)	6 (55)	23 (50)

^aIncludes 6 on steroids with unknown dose.

^bAmong 82 with a complication, there were 45 (55%) with secondary infections including 36 with sepsis; 44 (54%) with pneumonia; 34 (41%) with hemorrhagic complications; 27 (33%) with CNS complications; and 10 (12%) with other/multiple organ involvement.

^cIncludes positive Varicella-zoster virus (VZV) polymerase chain reaction (PCR), direct fluorescent antibody (DFA), immunoglobulin M (IGM), viral culture, Tzanck smear, including testing on autopsy specimens.

Table 4. Varicella Deaths among Varicella Vaccinated Persons (Fatal Breakthrough Varicella), 1996–2013 (N = 5 )

Case ID (year of death)	Age (years), Sex	Underlying Conditions/Medications	Varicella Vaccination	Clinical Course	Laboratory Testing
Patient A^14,15 (1997)	9, Female	Asthma; history of multiple hospitalizations with 4 requiring ventilation; on high-dose steroids (60 mg/day but steroid not specified)	1st dose at 8 y of age	Developed staph infection, sepsis, endocarditis, neurologic complications, disseminated intravascular coagulation, hepatitis, pancreatitis, and other complications	Positive VZV cultures from blood, tracheal aspirate, and rectal swabs
Patient B^11a (2004)	7, Female	Malignant ependymoma (midbrain tumor) and on dexamethasone (2 mg/day)	1st dose at 1 y of age	Rash with 250–500 lesions; developed varicella sepsis and thrombocytopenia	Wild-type-VZV DNA identified in skin vesicle specimen
Patient C^12 (2011)	4, Female	No known immunocompromising conditions; history of nasal septum perforation with subsequent recurrent sinusitis requiring prolonged courses of antibiotic therapy	1st dose at 13 months of age	Experienced frequent and intermittent episodes of vomiting, headaches, seizures, lethargy, low-grade fever, mental status changes, and poor interaction; no rash	Wild-type VZV DNA identified in brain tissue blocks
Patient D^13 (2012)	4, Female	Pre-B acute lymphoblastic leukemia on maintenance therapy (Vincristine/dexamethasone, administered every 12 weeks)	1st dose at 1 y of age	Developed generalized vesicular rash with abdominal pain and vomiting; developed fever, respiratory distress, hepatitis, coagulopathy, and thrombocytopenia	VZV identification not performed
Patient E (2013)	15, Male	T cell precursor ALL; on 20 mg/day Decadron; had received post consolidation chemotherapy (Vincristine) within 7 d of his admission to the hospital	1st dose at 2 y of age	Initially admitted for observation due to recent chemotherapy; developed rash on day 4 of hospitalization; developed multi-organ failure and died 4 d after rash onset	Wild-type VZV DNA identified in skin vesicle specimen

Note- VZV, varicella-zoster virus, ALL=acute lymphocytic leukemia.

^aIncluded in one of 3 deaths among vaccinated persons reported in Galea et al.¹¹