diff --git a/testinfra/plugin.py b/testinfra/plugin.py
index 707ff505..d1371dbb 100644
--- a/testinfra/plugin.py
+++ b/testinfra/plugin.py
@@ -15,7 +15,7 @@
 import sys
 import tempfile
 import time
-from typing import AnyStr
+from typing import AnyStr, cast
 
 import pytest
 
@@ -25,19 +25,19 @@
 
 
 @pytest.fixture(scope="module")
-def _testinfra_host(request):
-    return request.param
+def _testinfra_host(request: pytest.FixtureRequest) -> testinfra.host.Host:
+    return cast(testinfra.host.Host, request.param)
 
 
 @pytest.fixture(scope="module")
-def host(_testinfra_host):
+def host(_testinfra_host: testinfra.host.Host) -> testinfra.host.Host:
     return _testinfra_host
 
 
 host.__doc__ = testinfra.host.Host.__doc__
 
 
-def pytest_addoption(parser):
+def pytest_addoption(parser: pytest.Parser) -> None:
     group = parser.getgroup("testinfra")
     group.addoption(
         "--connection",
@@ -107,7 +107,7 @@ def pytest_addoption(parser):
     )
 
 
-def pytest_generate_tests(metafunc):
+def pytest_generate_tests(metafunc: pytest.Metafunc) -> None:
     if "_testinfra_host" in metafunc.fixturenames:
         if metafunc.config.option.hosts is not None:
             hosts = metafunc.config.option.hosts.split(",")
@@ -141,7 +141,7 @@ def __init__(self, out):
         self.total_time = None
         self.out = out
 
-    def pytest_runtest_logreport(self, report):
+    def pytest_runtest_logreport(self, report: pytest.TestReport) -> None:
         if report.passed:
             if report.when == "call":  # ignore setup/teardown
                 self.passed += 1
@@ -150,7 +150,7 @@ def pytest_runtest_logreport(self, report):
         elif report.skipped:
             self.skipped += 1
 
-    def report(self):
+    def report(self) -> int:
         if self.failed:
             status = b"CRITICAL"
             ret = 2