Sucuri fails on detecting this website hack and failed miserably: https://sitecheck.sucuri.net/results/mainedisasterbehavioralhealth.us6.list-manage.com#sitecheck-details
Quttera is the one to detect: index
Severity: Suspicious
Reason: Detected suspicious redirection to external web resources at HTTP level.
Details: Detected HTTP redirection to htxp://mailchimp.com/about/mcsv/.
File size[byte]: 0
File type: Unknown
Page/File MD5: 00000000000000000000000000000000
Scan duration[sec]: 0.001000 Set-Cookie: _AVESTA_ENVIRONMENT=prod; path=/
VT also forgets to flag this abuse: https://www.virustotal.com/nl/url/c2b79e1cfda0ac07360c948b728f2fcf174c3b47fe960dfa0f717c56df5c50ef/analysis/1438871713/
How to block hackers, read: http://www.mysecondmillion.com/alterego-block-mailchimp-hackers/
Also consider: http://us6.campaign-archive1.com.ipaddress.com/ and the official site: http://www.mainedisasterbehavioralhealth.com/
polonus