APPENDIX III-E: West Nile Virus Cases, U.S., 1999-2006

This appendix copied from the following websites:

http://www.cdc.gov/ncidod/dvbid/westnile/surv&controlCaseCount99_detailed.htm

http://www.cdc.gov/ncidod/dvbid/westnile/surv&controlCaseCount00_detailed.htm

http://www.cdc.gov/ncidod/dvbid/westnile/surv&controlCaseCount01_detailed.htm

http://www.cdc.gov/ncidod/dvbid/westnile/surv&controlCaseCount02_detailed.htm

http://www.cdc.gov/ncidod/dvbid/westnile/surv&controlCaseCount03_detailed.htm

http://www.cdc.gov/ncidod/dvbid/westnile/surv&controlCaseCount04_detailed.htm

http://www.cdc.gov/ncidod/dvbid/westnile/surv&controlCaseCount05_detailed.htm

http://www.cdc.gov/ncidod/dvbid/westnile/surv&controlCaseCount06_detailed.htm

1999 West Nile Virus Activity
in the United States

State	Encephalitis/Meningitis	Fever	Clinical/Unspecified	Total	Fatalities
New York	59	3	0	62	7
Total	59	3	0	62	7

West Nile encephalitis and West Nile meningitis are forms of severe disease that affect a person’s nervous system. Encephalitis refers to an inflammation of the brain, meningitis is an inflammation of the membrane around the brain and the spinal cord.
Click here for further explanation of WN meningitis and/or encephalitis.

West Nile fever refers to typically less severe cases that show no evidence of neuroinvasion. WN fever is considered a notifiable disease, however the number of cases reported (as with all diseases) may be limited by whether persons affected seek care, whether laboratory diagnosis is ordered and the extent to which cases are reported to health authorities by the diagnosing physician.

Other Clinical includes persons with clinical manifestations other than WN fever, WN encephalitis or WN meningitis, such as acute flaccid paralysis. Clinical/Unspecified cases are those for which sufficient clinical information was not provided.

Total Human Cases Reported to CDC- These numbers reflect both mild and severe human disease cases occurring between January 1, 1999 through December 31, 1999 that have been reported to ArboNET by state and local health departments. ArboNET is the national, electronic surveillance system established by CDC to assist states in tracking West Nile virus and other mosquito-borne viruses. Information regarding 1999 virus/disease activity is posted when such cases are reported to CDC.

Of the 62 cases, 59 (95%) were reported as West Nile meningitis or encephalitis (neuroinvasive disease), 3 (5%) were reported as West Nile fever (milder disease), and 0 (0%) were clinically Clinical/Unspecified at this time. Please refer to state health department web sites for further details regarding state case totals.

Note: The high proportion of neuroinvasive disease cases among reported cases of West Nile virus disease reflects surveillance reporting bias. Serious cases are more likely to be reported than mild cases. Also, the surveillance system is not designed to detect asymptomatic infections. Data from population-based surveys indicate that among all people who become infected with West Nile virus (including people with asymptomatic infections) less than 1% will develop severe neuroinvasive disease. See: Mostashari F, Bunning ML, Kitsutani PT, et al. Epidemic West Nile Encephalitis, New York, 1999: Results of a household-based seroepidemiological survey. Lancet 2001;358:261-264.

For Case Information:
1999|2000|2001|2002|2003|2004|2005|2006|2007

2000 West Nile Virus Activity
in the United States

State	Encephalitis/Meningitis	Fever	Clinical/Unspecified	Total	Fatalities
Connecticut	0	1	0	1	0
New Jersey	5	1	0	6	1
New York	14	0	0	14	1
Total	19	2	0	21	2

Total Human Cases Reported to CDC- These numbers reflect both mild and severe human disease cases occurring between January 1, 2001 through December 31, 2001 that have been reported to ArboNET by state and local health departments. ArboNET is the national, electronic surveillance system established by CDC to assist states in tracking West Nile virus and other mosquito-borne viruses. Information regarding 2001 virus/disease activity is posted when such cases are reported to CDC.

Of the 21 cases, 19 (90%) were reported as West Nile meningitis or encephalitis (neuroinvasive disease), 2 (10%) were reported as West Nile fever (milder disease), and 0 (0%) were clinically Clinical/Unspecified at this time. Please refer to state health department web sites for further details regarding state case totals.

2001 West Nile Virus Activity
in the United States

State	Encephalitis/Meningitis	Fever	Clinical/Unspecified	Total	Fatalities
Alabama	2	0	0	2	1
Connecticut	6	0	0	6	1
Florida	12	0	0	12	0
Georgia	6	0	0	6	1
Louisiana	1	0	0	1	0
Maryland	6	0	0	6	2
Massachusetts	3	0	0	3	1
New Jersey	12	0	0	12	1
New York	13	2	0	15	2
Pennsylvania	3	0	0	3	0
Total	64	2	0	66	9

West Nile encephalitis and West Nile meningitis are forms of severe disease

Total Human Cases Reported to CDC- These numbers reflect both mild and severe human disease cases occurring between January 1, 2001 through December 31, 2001 that have been reported to ArboNET by state and local health departments. ArboNET is the national, electronic surveillance system established by CDC to assist states in tracking West Nile virus and other mosquito-borne viruses. Information regarding 2001 virus/disease activity is posted when such cases are reported to CDC.

Of the 66 cases, 64 (97%) were reported as West Nile meningitis or encephalitis (neuroinvasive disease), 2 (3%) were reported as West Nile fever (milder disease), and 0 (1%) were clinically Clinical/Unspecified at this time. Please refer to state health department web sites for further details regarding state case totals.

2002 West Nile Virus Activity
in the United States

State	Encephalitis/Meningitis	Fever	Clinical/Unspecified	Total	Fatalities
Alabama	34	15	0	49	3
Arkansas	32	11	0	43	3
California	1	0	0	1	0
Colorado	6	8	0	14	0
Connecticut	10	6	1	17	0
Delaware	0	1	0	1	0
District of Columbia	14	19	1	34	1
Florida	28	0	0	28	2
Georgia	28	15	1	44	7
Illinois	553	328	3	884	64
Indiana	180	102	11	293	11
Iowa	27	27	0	54	2
Kansas	22	0	0	22	0
Kentucky	53	22	0	75	5
Louisiana	204	122	3	329	25
Maryland	22	14	0	36	7
Massachusetts	19	4	0	23	3
Michigan	557	54	3	614	51
Minnesota	16	32	0	48	0
Mississippi	162	29	1	192	12
Missouri	126	42	0	168	7
Montana	2	0	0	2	0
Nebraska	84	53	15	152	7
New Jersey	16	8	0	24	0
New York	68	12	2	82	5
North Carolina	2	0	0	2	0
North Dakota	3	11	3	17	2
Ohio	310	131	0	441	31
Oklahoma	16	4	1	21	2
Pennsylvania	42	20	0	62	7
Rhode Island	1	0	0	1	0
South Carolina	1	0	0	1	0
South Dakota	17	20	0	37	0
Tennessee	47	9	0	56	7
Texas	202	0	0	202	13
Vermont	0	1	0	1	0
Virginia	16	12	1	29	2
West Virginia	3	0	0	3	2
Wisconsin	22	26	4	52	3
Wyoming	0	2	0	2	0
Total	2946	1160	50	4156	284

Total Human Cases Reported to CDC- These numbers reflect both mild and severe human disease cases occurring between January 1, 2002 through December 31, 2002 that have been reported to ArboNET by state and local health departments. ArboNET is the national, electronic surveillance system established by CDC to assist states in tracking West Nile virus and other mosquito-borne viruses. Information regarding 2002 virus/disease activity is posted when such cases are reported to CDC.

Of the 4156 cases, 2946 (71%) were reported as West Nile meningitis or encephalitis (neuroinvasive disease), 1160 (28%) were reported as West Nile fever (milder disease), and 50 (1%) were clinically Clinical/Unspecified at this time. Please refer to state health department web sites for further details regarding state case totals.

2003 West Nile Virus Activity
in the United States

State	Encephalitis/Meningitis	Fever	Clinical/Unspecified	Total	Fatalities
Alabama	25	10	2	37	3
Arizona	7	2	4	13	1
Arkansas	23	2	0	25	0
California	2	1	0	3	0
Colorado	621	2326	0	2947	63
Connecticut	12	5	0	17	0
Delaware	12	4	1	17	2
District of Columbia	3	0	0	3	0
Florida	61	33	0	94	6
Georgia	27	21	2	50	4
Idaho	0	1	0	1	0
Illinois	30	24	0	54	1
Indiana	15	31	1	47	4
Iowa	81	65	1	147	6
Kansas	89	0	2	91	4
Kentucky	11	1	2	14	1
Louisiana	101	23	0	124	8
Maryland	49	23	1	73	8
Massachusetts	12	5	0	17	1
Michigan	14	4	1	19	2
Minnesota	48	100	0	148	4
Mississippi	34	38	15	87	1
Missouri	39	25	0	64	8
Montana	75	135	12	222	4
Nebraska	194	1741	7	1942	29
Nevada	2	0	0	2	0
New Hampshire	2	0	1	3	0
New Jersey	21	9	4	34	3
New Mexico	74	135	0	209	4
New York	57	12	2	71	11
North Carolina	16	8	0	24	2
North Dakota	94	523	0	617	5
Ohio	84	24	0	108	8
Oklahoma	56	23	0	79	0
Pennsylvania	145	90	2	237	8
Rhode Island	5	2	0	7	1
South Carolina	3	3	0	6	0
South Dakota	151	869	19	1039	14
Tennessee	21	5	0	26	1
Texas	431	289	0	720	37
Utah	0	1	0	1	0
Vermont	0	3	0	3	0
Virginia	19	1	6	26	1
West Virginia	1	1	0	2	0
Wisconsin	7	2	8	17	0
Wyoming	92	210	73	375	9
Total	2866	6830	166	9862	264

Total Human Cases Reported to CDC for 2003- These numbers reflect both mild and severe human disease cases occurring between Jan.1 -Dec. 31, 2003 that have been reported to ArboNET by state and local health departments. ArboNET is the national, electronic surveillance system established by CDC to assist states in tracking West Nile virus and other mosquito-borne viruses. Information regarding 2004 virus/disease activity will be posted when such cases are reported to CDC.

Of 9862 cases, 6830 (69%) were reported as West Nile fever (milder disease), 2866 (29%) were reported as West Nile meningitis or encephalitis (neuroinvasive disease) and 166 (2%) were clinically Clinical/Unspecified. Please refer to state health department web sites for further details regarding state case totals.

2004 West Nile Virus Activity
in the United States

State	Encephalitis/Meningitis	Fever	Clinical/Unspecified	Total	Fatalities
Alabama	15	1	0	16	0
Arizona	214	160	17	391	16
Arkansas	17	10	1	28	0
California	289	395	95	779	28
Colorado	41	250	0	291	4
Connecticut	0	1	0	1	0
District of Columbia	1	1	0	2	0
Florida	33	8	0	41	2
Georgia	14	7	0	21	1
Idaho	1	2	0	3	0
Illinois	29	30	1	60	4
Indiana	8	2	3	13	1
Iowa	13	9	1	23	2
Kansas	18	25	0	43	2
Kentucky	1	6	0	7	0
Louisiana	85	24	0	109	7
Maryland	10	6	0	16	0
Michigan	13	3	0	16	0
Minnesota	13	21	0	34	2
Mississippi	31	18	2	51	4
Missouri	27	9	0	36	2
Montana	2	3	1	6	0
Nebraska	7	46	0	53	0
Nevada	25	19	0	44	0
New Jersey	1	0	0	1	0
New Mexico	31	53	4	88	4
New York	7	3	0	10	0
North Carolina	3	0	0	3	0
North Dakota	2	18	0	20	2
Ohio	11	1	0	12	2
Oklahoma	16	6	0	22	3
Oregon	0	3	0	3	0
Pennsylvania	9	5	1	15	2
South Carolina	0	2	0	2	0
South Dakota	6	45	0	51	1
Tennessee	13	1	0	14	0
Texas	119	57	0	176	8
Utah	6	5	0	11	0
Virginia	4	0	1	5	1
Wisconsin	5	7	0	12	2
Wyoming	2	7	1	10	0
Total	1142	1269	128	2539	100

Total Human Cases Reported to CDC- These numbers reflect both mild and severe human disease cases occurring between January 1, 2004 through December 31, 2004 that have been reported to ArboNET by state and local health departments. ArboNET is the national, electronic surveillance system established by CDC to assist states in tracking West Nile virus and other mosquito-borne viruses. Information regarding 2004 virus/disease activity is posted when such cases are reported to CDC.

Of the 2539 cases, 1142 (45%) were reported as West Nile meningitis or encephalitis (neuroinvasive disease), 1269 (50%) were reported as West Nile fever (milder disease), and 128 (5%) were clinically Clinical/Unspecified at this time. Please refer to state health department web sites for further details regarding state case totals.

2005 West Nile Virus Activity
in the United States

State	Encephalitis/Meningitis	Fever	Other Clinical/Unspecified	Total	Fatalities
Alabama	6	4	0	10	2
Arizona	50	61	2	113	5
Arkansas	13	15	0	28	4
California	299	534	47	880	19
Colorado	21	85	0	106	2
Connecticut	4	2	0	6	1
Delaware	1	0	1	2	0
District of Columbia	3	2	0	5	0
Florida	10	11	0	21	1
Georgia	9	7	4	20	2
Idaho	3	10	0	13	0
Illinois	134	91	27	252	13
Indiana	10	2	11	23	1
Iowa	14	21	2	37	2
Kansas	17	8	0	25	1
Kentucky	5	0	0	5	1
Louisiana	117	54	0	171	11
Maryland	4	1	0	5	0
Massachusetts	4	2	0	6	1
Michigan	52	8	2	62	4
Minnesota	18	27	0	45	3
Mississippi	39	31	0	70	6
Missouri	17	13	0	30	3
Montana	8	17	0	25	0
Nebraska	55	133	0	188	5
Nevada	14	15	2	31	1
New Jersey	3	3	0	6	0
New Mexico	20	13	0	33	2
New York	30	8	0	38	4
North Carolina	2	2	0	4	0
North Dakota	12	74	0	86	0
Ohio	46	15	0	61	2
Oklahoma	17	14	0	31	1
Oregon	1	6	0	7	0
Pennsylvania	14	11	0	25	2
Rhode Island	1	0	0	1	0
South Carolina	5	0	0	5	1
South Dakota	35	193	1	229	2
Tennessee	15	3	0	18	1
Texas	128	67	0	195	11
Utah	21	31	0	52	1
Virginia	0	1	0	1	0
Wisconsin	11	6	0	17	2
Wyoming	6	6	0	12	2
Total	1294	1607	99	3000	119

Total Human Cases Reported to CDC: These numbers reflect both mild and severe human disease cases occurring between January 1, 2005 to December 31, 2005 as reported through May 5, 2006 that have been reported to ArboNET by state and local health departments. ArboNET is the national, electronic surveillance system established by CDC to assist states in tracking West Nile virus and other mosquito-borne viruses. Information regarding 2005 virus/disease activity is posted when such cases are reported to CDC.

Of the 3000 cases, 1294 (43%) were reported as West Nile meningitis or encephalitis (neuroinvasive disease), 1607 (54%) were reported as West Nile fever (milder disease), and 99 (3%) were clinically Clinical/Unspecified at this time. Please refer to state health department web sites for further details regarding state case totals.

2006 West Nile Virus Activity
in the United States

State	Encephalitis/ Meningitis	Fever	Other Clinical/Unspecified	Total	Fatalities
Alabama	8	0	0	8	0
Arizona	65	77	8	150	11
Arkansas	24	5	0	29	4
California	81	186	11	278	7
Colorado	66	279	0	345	7
Connecticut	7	2	0	9	1
District of Columbia	0	2	0	2	0
Florida	3	0	0	3	0
Georgia	2	5	1	8	1
Idaho	115	827	54	996	21
Illinois	122	69	24	215	10
Indiana	27	8	45	80	5
Iowa	21	13	3	37	0
Kansas	17	13	0	30	4
Kentucky	5	1	0	6	1
Louisiana	91	89	0	180	9
Maryland	9	1	1	11	1
Massachusetts	2	1	0	3	0
Michigan	43	10	2	55	7
Minnesota	31	34	0	65	3
Mississippi	89	94	0	183	14
Missouri	50	11	1	62	5
Montana	12	21	1	34	0
Nebraska	45	219	0	264	1
Nevada	34	76	14	124	1
New Jersey	2	2	1	5	0
New Mexico	3	5	0	8	1
New York	16	8	0	24	4
North Carolina	1	0	0	1	0
North Dakota	20	117	0	137	1
Ohio	36	12	0	48	4
Oklahoma	26	21	1	48	6
Oregon	7	50	12	69	2
Pennsylvania	8	1	0	9	2
South Carolina	1	0	0	1	0
South Dakota	38	75	0	113	3
Tennessee	16	6	0	22	1
Texas	233	121	0	354	32
Utah	56	102	0	158	5
Virginia	0	0	5	5	0
Washington	0	3	0	3	0
West Virginia	1	0	0	1	0
Wisconsin	11	10	0	21	1
Wyoming	15	40	10	65	2
Totals	1459	2616	194	4269	177

Total Human Cases Reported to CDC: These numbers reflect both mild and severe human disease cases occurring between January 1, 2006 to December 31, 2006 as reported through May 22, 2007 that have been reported to ArboNET by state and local health departments. ArboNET is the national, electronic surveillance system established by CDC to assist states in tracking West Nile virus and other mosquito-borne viruses. Information regarding 2006 virus/disease activity is posted when such cases are reported to CDC.

Of the 4269 cases, 1459 (34%) were reported as West Nile meningitis or encephalitis (neuroinvasive disease), 2616 (61%) were reported as West Nile fever (milder disease), and 194 (5%) were clinically unspecified at this time. Please refer to state health department web sites for further details regarding state case totals.